【单选题】【消耗次数：1】
PSS男女患病比约为：
①
1:2
②
1:3
③
1:7
④
1:9
⑤
1:10
参考答案：
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相关题目
【单选题】
设离散型随机变量（X，Y）的联合分布律为（X，Y）（1,1）（1,2）（1,3）（2,1）（2,2）（2,3）P1/61/91/181/3ab且X，Y相互独立，则
①
a=2/9, b=1/9
②
a=1/9, b=2/9
③
a=1/6, b=1/6
④
a=8/15, b=1/18
【单选题】
设A ={1，3，5，7}，B = {5, 7, 9，11}，则A∪B是（）
①
{1，3, 5}
②
{1,3，5，7}
③
{1, 3, 5, 7，9}
④
{1, 3, 5, 7，9, 11}
【单选题】
向量空间<imgwidth="216"height="28"src="data:image/png;base64,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"/>的维数等于（）
①
0
②
1
③
2
④
3
随机题目
【简答题】
设<img class="jc-formula" data-tex="A=\left( 1\quad -1\quad \quad 1\quad 2\\ 2\quad \quad 3\quad \quad 3\quad 2\\ 1\quad \quad 1\quad \quad 2\quad 1 \right) ,B=\left( 1\quad 3\quad -1\quad -2\\ 2\quad -1\quad 2\quad \quad 3\\ 3\quad 2\quad \quad 1\quad \quad 1\\ 1\quad -4\quad 3\quad \quad 5 \right) " src="https://huaweicloudobs.ahjxjy.cn/34300AEB8E343C28BD94B0D68BD6C284.png" style="vertical-align: middle;"/>，求<img class="jc-formula" data-tex="R(A),R(B)" src="https://huaweicloudobs.ahjxjy.cn/1D62A0EB9AE12B9D008D84666B3C7920.png" style="vertical-align: middle;"/>．
【简答题】
求方程组<img class="jc-formula" data-tex="\begin{ cases } x_{ 1 }-{ x }_{ 2 }-{ x }_{ 3 }+{ x }_{ 4 }=0 \\ { x }_{ 1 }-{ x }_{ 2 }+{ x }_{ 3 }-3{ x }_{ 4 }=0 \\ { x }_{ 1 }-{ x }_{ 2 }-2{ x }_{ 3 }+3{ x }_{ 4 }=0 \end{ cases }" src="https://huaweicloudobs.ahjxjy.cn/D4C08D0A4459C36BE868755327686B0E.png" style="vertical-align: middle;"/>的全部解。
【简答题】
求解方程组<img class="jc-formula" data-tex="\begin{ cases } { x }_{ 1 }-2{ x }_{ 2 }+3{ x }_{ 3 }-{ x }_{ 4 }=1 \\ 3{ x }_{ 1 }-5{ x }_{ 2 }+5x_{ 3 }-3{ x }_{ 4 }=2 \\ 2{ x }_{ 1 }-3{ x }_{ 2 }+2{ x }_{ 3 }-2{ x }_{ 4 }=1 \end{ cases }" src="https://huaweicloudobs.ahjxjy.cn/D2F7DBEDF74F0DA535C0BD6A61FA9854.png" style="vertical-align: middle;"/>