Question

要使5/x-1与4/x-2的值相等,则x=_____;当x=___,分式1/2x+1与1/2(x-4)互为倒数

Answer 1

1、要使5/x-1与4/x-2的值相等,则有5/(x-1)=4/(x-2)

所以5(x-2)=4(x-1)

即有5x-4x=-4+10

x=6

2、分式1/2x+1与1/2(x-4)互为倒数

则2x+1=1/2(x-4)

2(2x+1)(x-4)=1

4x^2-14x-8-1=0

4x^2-14x-9=0

解得x=7+-根号85