Question

tìm x
(3x+1)^2 = (x-1)^2

Answer 1

(3x+1)^2 = (x-1)^2

<=>(3x+1)²-(x-1)²=0

<=>(3x+1-x+1)(3x+1+x-1)=0

<=>(2x+2)4x=0

<=>2(x+1).4x=0

<=> 8x(x+1)=0

<=>8x=0 hoặc x+1=0

<=> x=0 hoặc x=-1

Answer 2

(3x+1)^2 = (x-1)^2

<=>(3x+1)²-(x-1)²=0

<=>(3x+1-x+1)(3x+1+x-1)=0

<=>(2x+2)4x=0

<=>2(x+1).4x=0

<=>x=0 hoặc x+1=0

<=>x=0 hoặc x=-1