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设二次型 f(x_1, x_2, x_3) = x^T A x 平方项的系数为 0,满足 Aalpha = 2alpha,其中 alpha = (1, 2, -
7.[福建2020适应性模拟]已知 tan alpha =2 ,则-|||-dfrac ({sin )^2alpha -(cos )^2alpha +2}(2{
[题目]若 sin alpha =dfrac (1)(3), 则 cos 2alpha = ()()-|||-
设随机变量 X sim N(mu, sigma^2), Y sim N(mu, sigma^2), 且设X,Y相互独立,则 Z_1 = alpha X + be
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4、判断 设向量 alpha =-|||-A-|||-B x
设有向量组 alpha_1, alpha_2, ldots, alpha_m,若对于任意一组不全为零的实数 k_1, k_2, ldots, k_m,都有 k_
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