已知a,b满足|a+1/5|+(a+b+7/10)^2=0.求(4a-b)^2-[8a(1-a)-(3a-b)(3a+b)]的值.

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已知a,b满足|a+1/5|+(a+b+7/10)^2=0.求(4a-b)^2-[8a(1-a)-(3a-b)(3a+b)]的值.
已知a,b满足|a+1/5|+(a+b+7/10)^2=0.求(4a-b)^2-[8a(1-a)-(3a-b)(3a+b)]的值.

已知a,b满足|a+1/5|+(a+b+7/10)^2=0.求(4a-b)^2-[8a(1-a)-(3a-b)(3a+b)]的值.
a=-0.2
b=-0.5
2.62

由|a+1/5|+(a+b+7/10)^2=0. 得,
|a+1/5|=0, 所以 a=-1/5
a+b+7/10=0, a=-1/5 所以 b =-1/2
(4a-b)^2-[8a(1-a)-(3a-b)(3a+b)]
=a(a-8b-8)
=21/25

由|a+1/5|+(a+b+7/10)^2=0. 得,
|a+1/5|=0, 所以 a=-1/5
a+b+7/10=0, a=-1/5 所以 b =-1/2
(4a-b)^2-[8a(1-a)-(3a-b)(3a+b)]
=a(a-8b-8)
=21/25