Question

5道初一较难计算题1.(a-2b+c)(a+2b-c)-(a+b+c)∧22.(x-y)(x+y)(x∧2+y∧2)(x

Answer 1

1.(a-2b+c)(a+2b-c)-(a+b+c)∧2=-5b^2-2c^2-2ab+2bc-2ac2.(x-y)(x+y)(x∧2+y∧2)(x∧4+y∧4) =x^8-y^83.求（2x∧5-4x∧4-3x∧3+7x∧2-x-6)(3x∧7-2x∧5-5x∧4+2x∧3+x∧2-2x+1)中x∧9的系数 系数是194.若a∧2+b∧2+c...