A 可逆，则 ^-1|=dfrac (1)(|A|)-|||-__（）A 对B 错

设矩阵A与B相似,且A与B可逆,则 ^Tsim (B)^T,-|||-^-1sim (B)^-1 sim (B)^*-|||-A 对-|||-B 错

8.已知 (A)=dfrac (1)(4) ,(B|A)=dfrac (1)(3) ,(B)=dfrac (1)(6) ,则-|||-P(A|B)=-|||-A

(B|A)=dfrac (1)(3) .(A|B)=dfrac (1)(2), 则-|||-(Acup B)= __ 。

3.已知 (A)=dfrac (1)(3), (B|A)=dfrac (1)(4) ,(A|B)=dfrac (1)(6), 则 (Acup B)= __

若a,b,c均为正数,且a+b+c=10, 则dfrac (1)(a)+dfrac (1)(b)+dfrac (1)(c)的最小值为( )A 1 B dfrac

)-|||-则 cot (XY)=() 。-|||-A .-dfrac (1)(18) .-|||-B .dfrac (1)(18)-|||-C .dfrac

(5)设 (A)=dfrac (1)(3), (B)=dfrac (1)(4), (Acup B)=dfrac (1)(2), 则 (overline (A)c

判断题-|||-.(ln x)=dfrac (1)(x)-|||-A 对-|||-B 错

1.已知 (A)=P(B)=dfrac (1)(3) (A|B)=dfrac (1)(6), 则P(AB)= () .-|||-

A,B均为n阶可逆矩阵，则A+B也是可逆矩阵.A.对B.错11.（判断题，5.0分）A,B均为n阶可逆矩阵，则A+B也是可逆矩阵.A.对B.错