1.2x(x-5)-(x+3)(x-2) 2.(-3xy²)²·(-xy)三次方
问题描述：
1.2x(x-5)-(x+3)(x-2) 2.(-3xy²)²·(-xy)三次方
3.(1/9)负一次方+(-2)三次方+3-（1-π）º
4.(2x-1)²+(1-3x)²=13(x-1)(x+1)求x的值
5.已知：x+y=-6,xy=2,求代数式(x-y)²的值,为______?
答
1.2x(x-5) - (x+3)(x-2)= 2x² - 10x - (x² + x - 6)= x² - 11x + 62.(-3xy²)² × (-xy)^3= 9x²y^4 × (-x^3y^3)= -9(x^5)(y^7)3.(1/9)^(-1) + (-2)^3 + 3 - (1-π)º= 9 -8 + 3 -...