第756题:再次回顾
方程5x \dfrac{5}{x}x5−5x(x+1) -\dfrac{5}{x(x+1)}−x(x+1)5=1=1=1 的解是多少?
关于分式的裂项,再回顾一下,务必记住:
nx(x+1)\dfrac{n}{x(x+1)}x(x+1)n=== nx−\dfrac{n}{x}-xn− nx+1\dfrac{n}{x+1}x+1n
1x(x+n)\dfrac{1}{x(x+n)}x(x+n)1=1n=\dfrac{1}{n}=n1(1x−1x+n) (\dfrac{1}{x}-\dfrac{1}{x+n})(x1−x+n1)