Solve for x
x=-\left(\sqrt{2}+1\right)\approx -2.414213562
x=\sqrt{2}-1\approx 0.414213562
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\left(x+1\right)x+x+1=2
Variable x cannot be equal to -1 since division by zero is not defined. Multiply both sides of the equation by x+1.
x^{2}+x+x+1=2
Use the distributive property to multiply x+1 by x.
x^{2}+2x+1=2
Combine x and x to get 2x.
x^{2}+2x+1-2=0
Subtract 2 from both sides.
x^{2}+2x-1=0
Subtract 2 from 1 to get -1.
x=\frac{-2±\sqrt{2^{2}-4\left(-1\right)}}{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\left(-1\right)}}{2}
Square 2.
x=\frac{-2±\sqrt{4+4}}{2}
Multiply -4 times -1.
x=\frac{-2±\sqrt{8}}{2}
Add 4 to 4.
x=\frac{-2±2\sqrt{2}}{2}
Take the square root of 8.
x=\frac{2\sqrt{2}-2}{2}
Now solve the equation x=\frac{-2±2\sqrt{2}}{2} when ± is plus. Add -2 to 2\sqrt{2}.
x=\sqrt{2}-1
Divide -2+2\sqrt{2} by 2.
x=\frac{-2\sqrt{2}-2}{2}
Now solve the equation x=\frac{-2±2\sqrt{2}}{2} when ± is minus. Subtract 2\sqrt{2} from -2.
x=-\sqrt{2}-1
Divide -2-2\sqrt{2} by 2.
x=\sqrt{2}-1 x=-\sqrt{2}-1
The equation is now solved.
\left(x+1\right)x+x+1=2
Variable x cannot be equal to -1 since division by zero is not defined. Multiply both sides of the equation by x+1.
x^{2}+x+x+1=2
Use the distributive property to multiply x+1 by x.
x^{2}+2x+1=2
Combine x and x to get 2x.
\left(x+1\right)^{2}=2
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{2}
Take the square root of both sides of the equation.
x+1=\sqrt{2} x+1=-\sqrt{2}
Simplify.
x=\sqrt{2}-1 x=-\sqrt{2}-1
Subtract 1 from both sides of the equation.
Examples
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{ 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}