Question

(x+1)/(x+2)+(x+4)/(x+5)=(x+2)/(x+3)+(x+3)/(x+4)

Answer 1

兄弟左右拆分，然后相减，你看不出答案？难道你想要的是答案，不是解题方法？

Answer 2

3/6 2/6 5/6 7/6 12/6，（19/6），（31/6）

（1+1/2)X(1-1/2)X(1+1/3)X(1-1/3)X(1+1/4)X(1-1/4)X(1+1/5)X(1-1/5)=（3/2)X(1/2)X(4/3)X(2/3)X(5/4)X(3/4)X(6/5)X(4/5)=（1/2)×（6/5)=3/5

(1+1/2)X(1-1/2)X(1+1/3)X(1-1/3)X......X(1+1/99)X(1-1/99)
=1/2*100/99
=50/99

Answer 3

(x+1)/(x+2)=1-1/(x+2)
(x+4)/(x+5)=1-1/(x+5)
(x+2)/(x+3)=1-1/(x+3)
(x+3)/(x+4) =1-1/(x+4)
1/(x+2)+1/(x+5)=1/(x+3)+1/(x+4)
(2x+7)/(x^2+7x+10)=(2x+7)/(x^+7x+12)
2x+7=0或 x^2+7x+10=x^2+7x+12
2x+7=0
x=-7/2