x²-64y²分之2x 减 x-8y分之1

问题描述:

x²-64y²分之2x 减 x-8y分之1

2x/(x²-64y²) - 1/(x-8y) 根据公式:a²-b²=(a+b)(a-b)
=2x/(x+8y)(x-8y) - 1/(x-8y) 通分
=2x/(x+8y)(x-8y) - (x-8y)/(x+8y)(x-8y)
=(2x-x+8y)/(x+8y)(x-8y)
=(x+8y)/(x+8y)(x-8y)
=1/(x-8y)