Solve for x
x=-1
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x^{2}+2x+1-\left(x+1\right)\left(x-1\right)=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-\left(x^{2}-1\right)=0
Consider \left(x+1\right)\left(x-1\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 1.
x^{2}+2x+1-x^{2}+1=0
To find the opposite of x^{2}-1, find the opposite of each term.
2x+1+1=0
Combine x^{2} and -x^{2} to get 0.
2x+2=0
Add 1 and 1 to get 2.
2x=-2
Subtract 2 from both sides. Anything subtracted from zero gives its negation.
x=\frac{-2}{2}
Divide both sides by 2.
x=-1
Divide -2 by 2 to get -1.
Examples
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y = 3x + 4
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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
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