Solve for x
x=-1
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x^{2}-2x+1+4x=0
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-1\right)^{2}.
x^{2}+2x+1=0
Combine -2x and 4x to get 2x.
a+b=2 ab=1
To solve the equation, factor x^{2}+2x+1 using formula x^{2}+\left(a+b\right)x+ab=\left(x+a\right)\left(x+b\right). To find a and b, set up a system to be solved.
a=1 b=1
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. The only such pair is the system solution.
\left(x+1\right)\left(x+1\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
\left(x+1\right)^{2}
Rewrite as a binomial square.
x=-1
To find equation solution, solve x+1=0.
x^{2}-2x+1+4x=0
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-1\right)^{2}.
x^{2}+2x+1=0
Combine -2x and 4x to get 2x.
a+b=2 ab=1\times 1=1
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx+1. To find a and b, set up a system to be solved.
a=1 b=1
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. The only such pair is the system solution.
\left(x^{2}+x\right)+\left(x+1\right)
Rewrite x^{2}+2x+1 as \left(x^{2}+x\right)+\left(x+1\right).
x\left(x+1\right)+x+1
Factor out x in x^{2}+x.
\left(x+1\right)\left(x+1\right)
Factor out common term x+1 by using distributive property.
\left(x+1\right)^{2}
Rewrite as a binomial square.
x=-1
To find equation solution, solve x+1=0.
x^{2}-2x+1+4x=0
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-1\right)^{2}.
x^{2}+2x+1=0
Combine -2x and 4x to get 2x.
x=\frac{-2±\sqrt{2^{2}-4}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 2 for b, and 1 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-2±\sqrt{4-4}}{2}
Square 2.
x=\frac{-2±\sqrt{0}}{2}
Add 4 to -4.
x=-\frac{2}{2}
Take the square root of 0.
x=-1
Divide -2 by 2.
x^{2}-2x+1+4x=0
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-1\right)^{2}.
x^{2}+2x+1=0
Combine -2x and 4x to get 2x.
\left(x+1\right)^{2}=0
Factor x^{2}+2x+1. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(x+1\right)^{2}}=\sqrt{0}
Take the square root of both sides of the equation.
x+1=0 x+1=0
Simplify.
x=-1 x=-1
Subtract 1 from both sides of the equation.
x=-1
The equation is now solved. Solutions are the same.
Examples
Quadratic equation
{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}