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

问题描述:

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

1/(X+2)-1/(x+3)=1/(x+4)-1/(x+5) 即1/[(x+2)(x+3)]=1/[(x+4)(x+5)] 所以(x+2)(x+3)=(x+4)(x+5) 即5x+6=9x+20 故4x=-14 x=-7/2