计算(1)3x/8y×16y²/27x² (2)(2xy-x²)÷x-2y/xy 2x-6/x²-4x+4×2x-4/x-3
问题描述:
计算(1)3x/8y×16y²/27x² (2)(2xy-x²)÷x-2y/xy 2x-6/x²-4x+4×2x-4/x-3
答
(1)3x/8y×16y²/27x²
=3×16xy²/(8×27x² y)
=2y/(9x)
(2)(2xy-x²)÷x-2y/xy ? 2x-6/x²-4x+4×2x-4/x-3
有一符号不清楚
答
(1)3x/8y×16y²/27x² =(3/8×16/27)×(y/x)=2y/9x(2)(2xy-x²)÷x-2y/xy =x(2y-x)×[xy/(x-2y)]=-x²y (3) 2x-6/x²-4x+4×2x-4/x-3=2(x-3)/(x-2)²×2(x-2)/(x-3)=4/(x-2)