(x+1)*(x+3)=x^2+11

解方程(x+1)*(x+3)=x^2+11

解题(x+1)*(x+3)=x^2+11 方程

简化
(x + 1)(x + 3) = x2 + 11

重新排序条件:
(1 + x)(x + 3) = x2 + 11

重新排序条件:
(1 + x)(3 + x) = x2 + 11

乘以 (1 + x) * (3 + x)
(1(3 + x) + x(3 + x)) = x2 + 11
((3 * 1 + x * 1) + x(3 + x)) = x2 + 11
((3 + 1x) + x(3 + x)) = x2 + 11
(3 + 1x + (3 * x + x * x)) = x2 + 11
(3 + 1x + (3x + x2)) = x2 + 11

结合相似条件: 1x + 3x = 4x
(3 + 4x + x2) = x2 + 11

重新排序条件:
3 + 4x + x2 = 11 + x2

增加 '-1x2' 到方程的每一侧.
3 + 4x + x2 + -1x2 = 11 + x2 + -1x2

结合相似条件: x2 + -1x2 = 0
3 + 4x + 0 = 11 + x2 + -1x2
3 + 4x = 11 + x2 + -1x2

结合相似条件: x2 + -1x2 = 0
3 + 4x = 11 + 0
3 + 4x = 11

解：
3 + 4x = 11

求解变量 'x'.

移动所有含x 的放右边，所有其它条件放左边.

增加 '-3' 到方程的每一侧.
3 + -3 + 4x = 11 + -3

结合相似条件: 3 + -3 = 0
0 + 4x = 11 + -3
4x = 11 + -3

结合相似条件: 11 + -3 = 8
4x = 8

两边除以 '4'.
x = 2

简化
x = 2