17.
(A)1
(B)2
(C)3
(D)4
(E)5
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統計: A(10), B(1), C(4), D(2), E(0) #462880
統計: A(10), B(1), C(4), D(2), E(0) #462880
詳解 (共 2 筆)
#996335
(a+bi)(2+6i)=-80--->2a+6ai+2bi_6b=-80--->(6a+2b)i+(2a-6b)=-80
所以6a+2b=0......(1), 2a-6b=-80......(2)
由(1)(2)解䏈立得(a,b)=(-4,12)
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