x+2/x+3-x+1/x+2=x+8/x+9-x+7/x+8
问题描述:
x+2/x+3-x+1/x+2=x+8/x+9-x+7/x+8
答
(x+2)/(x+3)-(x+1)/(x+2)=(x+8)/(x+9)-(x+7)/(x+8)(x+2)²/[(x+2)(x+3)]-(x+1)(x+3)/[(x+2)(x+3)]=(x+8)²/[(x+8)(x+9)]-(x+7)(x+9)/[(x+8)(x+9)][(x+2)²-(x+1)(x+3)]/[(x+2)(x+3)]=[(x+8)²-(x+7)...