计算 (-2ab²)²·(3a²b-2ab-1)4(a-b)²-(2a+b)-(b+2a) (1+x-y)(x+y-1) (x+3y)(x²+9y²)(x-3y)急!!!!!!
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计算 (-2ab²)²·(3a²b-2ab-1)4(a-b)²-(2a+b)-(b+2a) (1+x-y)(x+y-1) (x+3y)(x²+9y²)(x-3y)急!!!!!!
计算 (-2ab²)²·(3a²b-2ab-1)
4(a-b)²-(2a+b)-(b+2a) (1+x-y)(x+y-1) (x+3y)(x²+9y²)(x-3y)
急!!!!!!
计算 (-2ab²)²·(3a²b-2ab-1)4(a-b)²-(2a+b)-(b+2a) (1+x-y)(x+y-1) (x+3y)(x²+9y²)(x-3y)急!!!!!!
(-2ab²)²·(3a²b-2ab-1)
=4a²b^4·(3a²b-2ab-1)
=12a²b^5-8a²b^5-4a²b^4
4(a-b)²-(2a+b)-(b+2a)
=a²-2ab+b²-2a-b-b-2a
=a²-2ab+b²-4a-2b
(1+x-y)(x+y-1)
=x-(1-y)²
=x-1+2y-y²
(x+3y)(x²+9y²)(x-3y)
=(x²-9y²)(x²+9y²)
=x^4-81y^4
4(a-b)²-(2a+b)-(-b+2a)
=4(a-b)²-2a-b+b-2a
=4(a-b)²-4a
=4[(a-b)²-a]
=4(a²-2ab+b²-a)