若(a+1)²+/b-3/=0,求(a+2b)²-(2a+b)(a-b)-2(a-b)(a+b)的值
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若(a+1)²+/b-3/=0,求(a+2b)²-(2a+b)(a-b)-2(a-b)(a+b)的值
若(a+1)²+/b-3/=0,求(a+2b)²-(2a+b)(a-b)-2(a-b)(a+b)的值
若(a+1)²+/b-3/=0,求(a+2b)²-(2a+b)(a-b)-2(a-b)(a+b)的值
∵(a+1)²+/b-3/=0
∴a+1=0
b-3=0
∴a=-1
b=3
(a+2b)²-(2a+b)(a-b)-2(a-b)(a+b)
=a²+4ab+4b²-(2a²-ab-b²)-2(a²-b²)
=a²+4ab+4b²-2a²+ab+b²-2a²+2b²
=-3a²+5ab+7b²
=-3-15+7
=-11
a=-1,b=3
化简=-3a^2+7b^2+5ab代入得45
/b-3/是什么
由两个非负数之和为零得,a+1=0,b-3=0,可得,a=-1,b=3,带入可以得到所求数值