548 lines
5.3 KiB
Plaintext
548 lines
5.3 KiB
Plaintext
ans
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13512
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$2$
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13513
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$x=\mu$
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13514
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可能异面, 可能相交
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13515
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$\dfrac{y^2}{15}+\dfrac{x^2}{16}=1$, $x\ne 0$
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13516
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$[1,15]$
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13517
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$-\dfrac 13$
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13518
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$\dfrac 43$
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13519
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$(-\infty,-1]\cup [3,+\infty)$
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13520
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$\sqrt{3}$
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13521
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$\pi$
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13522
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A
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13523
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D
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13524
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B
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13525
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(1) $\dfrac{5}{12}\text{h}$; (2) 能, $v$的取值范围为$(\dfrac{9\sqrt{3}}2,\dfrac{\sqrt{559}}3]$
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13526
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(1) 证明略; (2) $\dfrac{a_1}{a_2}\le \dfrac{a_1+a_3+\cdots+a_{2n-1}}{a_2+a_4+\cdots+a_{2n}}$, 当且仅当$n=1$或$d=0$时成立等号; (3) $2023^2$
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13527
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$\{(0,1),(2,5)\}$
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13528
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$x>1$且$y>1$
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13529
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$\sqrt{2}$
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13530
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$(-\infty,-8]\cup [2,+\infty)$
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13531
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$[-2,2]$
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13532
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$\dfrac 13$
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13533
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$\dfrac{4\pi}{3}$
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13534
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$20$
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13535
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\textcircled{3}\textcircled{4}
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13536
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\textcircled{1}\textcircled{3}\textcircled{4}
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13537
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B
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13538
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C
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13539
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D
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13540
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(1) 甲与乙的平均数分别为$7$和$7$; (2) 甲与乙的方差分别为$3$和$1.2$; (3) 两人射击水平相当, 甲的发挥更稳定
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13541
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(1) $\dfrac 12$; (2) $\dfrac{4\sqrt{5}}5$
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13542
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$3.5$
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13543
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$\dfrac{20}{11}$
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13544
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$a=\pm 1$
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13545
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$-17$
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13546
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$0.7$
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13547
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$5$
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13548
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$6\sqrt{3}$
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13549
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$0.6$
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13550
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$2\pi^2+16\pi$
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13551
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$\dfrac 83$
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13552
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C
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13553
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C
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13554
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B
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13555
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(1) $f(x)=\begin{cases}2^x-1+\log_2 (x+1), & x\ge 0, \\ 1-2^{-x}-\log_2(-x+1), & x<0;\end{cases}$ (2) $f(x)=-2^{x-2}+1-\log_2(x-1)$, $1<x\le 3$
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13556
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(1) $6$; (2) $-4$
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13557
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$(-\infty,-1)\cup (1,+\infty)$
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13558
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$240$
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13559
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$\dfrac 92$
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13560
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$(-\dfrac 32,+\infty)$
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13561
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$x+3y=0$或$x+y-4=0$
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13562
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$\dfrac 52$
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13563
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$\dfrac{\sqrt{5}+1}4$
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13564
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$\dfrac{1}{15}$
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13565
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$4$
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13566
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$\dfrac{3\sqrt{5}}5$
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13567
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B
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13568
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D
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13569
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D
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13570
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(1) $\chi^2=24>6.635$, 有$99.9\%$的把握认为患该疾病群体与为患该疾病群体的卫生习惯有差异; (2) 证明略, $R$的估计值为$6$
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13571
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(1) $y=2x$; (2) $(-\infty,-1)$
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13572
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$-\dfrac 12$
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13573
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$2\pi$
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13574
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$\dfrac{\sqrt{6}}2a^2$
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13575
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$3x-y-2=0$
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13576
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$-\dfrac{3}{25}\overrightarrow{b}$
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13577
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$-2$
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13578
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$\dfrac{2\sqrt{5}}5$
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13579
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$[\dfrac 54,\dfrac{3\sqrt{17}}4]$
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13580
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$77$
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13581
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$4$
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13582
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A
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13583
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B
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13584
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D
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13585
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(1) $0.89$; (2) $0.0014$
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13586
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(1) $x^2-\dfrac{y^2}{3}=1$; (2) 证明略
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13587
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$\{1,2\}$
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13588
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$2$
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13589
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$6$
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13590
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$3$
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13591
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$5$
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13592
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$-\sqrt{2}$
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13593
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$\dfrac 16$
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13594
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$-28$
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13595
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$0.14$
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13596
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$2$
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13597
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$\ln 2$
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13598
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$\dfrac{\sqrt{13}}2$
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13599
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A
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13600
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C
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13601
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C
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13602
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B
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13603
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(1) $\dfrac\pi 6$; (2) $6+6\sqrt{3}$
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13604
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(1) 证明略; (2) $\dfrac{\sqrt{6}}8$
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13605
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(1) $X\sim \begin{pmatrix} 0 & 20 & 100\\ 0.2 & 0.32 & 0.48\end{pmatrix}$; (2) 应选择先回答B类问题
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13606
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(1) $\dfrac{x^2}{25}+\dfrac{y^2}{9}=1$; (2) $2\sqrt{2}+\sqrt{17}$; (3) 定值为$34$
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13607
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(1) $y=x$; (2) 在$[0,+\infty)$上是严格增函数; (3) 证明略
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13608
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$1$
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13609
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$[\dfrac 12,1]$
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13610
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$2\sqrt{3}$
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13611
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$x\le \dfrac{a+b}{2}$, 等号成立当且仅当$a=b$
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13612
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$2x-y+1=0$
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13613
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$\dfrac{3\pi}{4}$
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13614
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$115$
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13615
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$-1$
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13616
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如$x^2+(y-2)^2=1$等(答案不唯一)
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13617
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$(0,-4)$
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13618
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$72$
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13619
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$\dfrac 78$
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13620
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B
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13621
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A
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13622
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C
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13623
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C
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13624
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(1) $\dfrac 13$; (2) 证明略
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13625
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(1) $a_n=3n-1$; (2) $S_n=\dfrac{21}{4}-\dfrac{6n+7}{4\cdot 3^{n-1}}$
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13626
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(1) $V=x(3-2x)^2$, $x\in (0,\dfrac 32)$; (2) 当$x=\dfrac 12$时, $V$取到最大值$2$
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13627
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(1) 最小正周期为$\pi$, 取值范围为$[-1,2]$; (2) $\sqrt{3}$
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13628
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(1) $2$; (2) 双曲线方程为$x^2-\dfrac{y^2}{3}=1$, 过顶点$(2,0)$与$(-1,0)$
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13629
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$4$或$-6$
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13630
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$(\dfrac\pi 6,\dfrac{5\pi}6)$
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13631
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$44$
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13632
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$41$
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13633
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$1$
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13634
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$24$
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13635
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$\dfrac{7\sqrt{3}}3\pi$
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13636
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$20$
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13637
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$2.5$
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13638
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$76$元
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13639
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$p_1$,$p_4$
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13640
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$\dfrac 34$
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13641
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D
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13642
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B
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13643
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C
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13644
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B
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13645
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证明略
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13646
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(1) $\dfrac\pi 3$; (2) $(6,12]$
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13647
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(1) $0.6$; (2) $x\sim \begin{pmatrix}0 & 10 & 20 & 30\\0.16 & 0.44 & 0.34 & 0.06\end{pmatrix}$, $E[X]=13$
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13648
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(1) $\dfrac{x^2}3+y^2=1$; (2) $\sqrt{6}$; (3) $1$
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13649
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(1) 在$(-1,1)$上是严格增函数, 在$(1,+\infty)$上是严格减函数; (2) $(-\infty,0]$; (3) 证明略
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13650
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$\{(0,0),(1,0),(-1,0)\}$
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13651
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$7$
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13652
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$-2$
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13653
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$0$
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13654
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$\dfrac{6\pi}{5}$
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13655
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$0.75$
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13656
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$(-6,2)$
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13657
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$\dfrac{2\sqrt{3}}3$
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13658
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$\dfrac{16}3$
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13659
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$\dfrac\pi 6$
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13660
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\textcircled{1}\textcircled{2}\textcircled{4}
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13661
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$12120$
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13662
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B
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13663
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B
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13664
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D
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13665
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D
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13666
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(1) $1$; (2) $\arcsin\dfrac{\sqrt{3}}4$
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13667
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(1) $\sqrt{7}$; (2) $-1-\dfrac{\sqrt{3}}2$
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13668
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(1) $(x-2)^2+y^2=\dfrac{12}7$; (2) $\dfrac{3\sqrt{2}}2$或$\dfrac{\sqrt{2}}2$
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13669
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(1) $\dfrac 25$; (2) $X\sim \begin{pmatrix} 0 & 1 & 2 \\ \dfrac{6}{25} & \dfrac{13}{25} & \dfrac{6}{25}\end{pmatrix}$; (3) 不认为人数有变化, 理由略
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13670
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(1) $y=x-1$; (2) $(-\infty,\dfrac{3}{2}]$; (3) $(-\infty,\dfrac{\sqrt{2}}2)$
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13671
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$1$
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13672
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$3$
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13673
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$\dfrac 12$
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13674
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$(0,2)$
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13675
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$2$
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13676
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$0.57$
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13677
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$\dfrac 72+\sqrt{6}$
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13678
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$\dfrac\pi 3$或$\dfrac{2\pi}3$
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13679
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$\sqrt{5}$
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13680
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$\dfrac{7\sqrt{3}}3$
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13681
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$\dfrac 83$
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13682
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$\dfrac 32$
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13683
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A
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13684
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C
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13685
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A
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13686
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B
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13687
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(1) 证明略; (2) $\dfrac\pi 6$
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13688
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(1) 证明略; (2) $(\dfrac 94,\dfrac{15}4)$
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13689
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(1) $l=\dfrac{1}{\sin \theta}+\dfrac{1}{\cos\theta}+\dfrac{1}{\sin\theta\cdot \cos\theta}$, $\theta\in (\dfrac\pi 6,\dfrac\pi 3)$; (2) $2+2\sqrt{2}$, 此时$\theta=\dfrac\pi 4$
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13690
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(1) $\dfrac{\sqrt{2}}2$; (2) $t=\dfrac{\sqrt{6}}3b$
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13691
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(1) $a=1$, $b=0$; (2) $3$; (3) 证明略
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