X平方=(3x+1)平方 解方程

x^2 = (3x+1)^2
x^2 - (3x+1)^2 = 0
[x + (3x+1)] * [x - (3x+1)] = 0
(4x + 1) * (-2x - 1) = 0
(4x + 1) * (2x + 1) = 0
4x + 1 = 0 或 2x + 1 = 0
x = -1/4 或 x = -1/2

先展开括号,得到x方=9x方+6x方+1 然后8x方+6x方+1=0 最后用公式得到X1=-1/4 X2=-1/2

x=-0.5或-0.25