计算 ①(x-y)(-y-x) ②(x+2)(x-2)(x²+4)
计算:(3x-4y)-[-(2y+x)+(x-3y)]-6x
计算:1/(2x) - 1/(x+y)((x+y)/(2x) - x - y)
计算4(x+y)^5(x-y)^4÷[2(x+y)³*(y-x)²]
(x-2y)²+(2x-4y)(x+y)+(x+y)²
计算 1.(-2x)^3-3x乘(x-2x^2) 2.【(x+2y)^2-(x-2y)(x+2y)】÷4y
计算:(1)2/(x+y)+4y/x²-y²(2)x²/x+y-x+y
计算:(3x-y)2-(2x+y)2+5x(y-x)
计算①(1+x+2y)^2 ②(2x-7y)(3x+4y-1)
运用乘法公式计算:(1)(x-y)(x+y)-(2x-y)²
计算:①-x·(y-x)³·(x-y)的四次方 ②(x-y)²·(y-x)³·(x-y)的
计算4xy+(x-2y)的平方+(x+3y)(3y-x)
计算:(x-4y)(2x+3y)-(x+2y)(x-y).