依题意,得
a+b=0,cd=1,x=±5
∴(1)当X=5时,
x²-(a+b+cd)x-cd
=5²-(0+1)×5-1
=25-5-1
=14
(2)当X=-5时,
x²-(a+b+cd)x-cd
=(-5)²-(0+1)×(-5)-1
=25+5-1
=29
依题意,得
a+b=0,cd=1,x=±5
∴(1)当X=5时,
x²-(a+b+cd)x-cd
=5²-(0+1)×5-1
=25-5-1
=14
(2)当X=-5时,
x²-(a+b+cd)x-cd
=(-5)²-(0+1)×(-5)-1
=25+5-1
=29