Solve for x
x=-\frac{\sqrt{30}}{6}-1\approx -1.912870929
x=\frac{\sqrt{30}}{6}-1\approx -0.087129071
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1+2x+x^{2}+\left(4-\left(-x+3\right)\right)^{2}=\frac{5}{3}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(-1-x\right)^{2}.
1+2x+x^{2}+\left(4-\left(-x\right)-3\right)^{2}=\frac{5}{3}
To find the opposite of -x+3, find the opposite of each term.
1+2x+x^{2}+\left(1-\left(-x\right)\right)^{2}=\frac{5}{3}
Subtract 3 from 4 to get 1.
1+2x+x^{2}+1+2\left(-\left(-x\right)\right)+\left(-\left(-x\right)\right)^{2}=\frac{5}{3}
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(1-\left(-x\right)\right)^{2}.
1+2x+x^{2}+1+2\left(-\left(-x\right)\right)+\left(-x\right)^{2}=\frac{5}{3}
Calculate -\left(-x\right) to the power of 2 and get \left(-x\right)^{2}.
2+2x+x^{2}+2\left(-\left(-x\right)\right)+\left(-x\right)^{2}=\frac{5}{3}
Add 1 and 1 to get 2.
2+2x+x^{2}+2\left(-\left(-x\right)\right)+x^{2}=\frac{5}{3}
Calculate -x to the power of 2 and get x^{2}.
2+2x+2x^{2}+2\left(-\left(-x\right)\right)=\frac{5}{3}
Combine x^{2} and x^{2} to get 2x^{2}.
2+2x+2x^{2}+2\left(-\left(-x\right)\right)-\frac{5}{3}=0
Subtract \frac{5}{3} from both sides.
\frac{1}{3}+2x+2x^{2}+2\left(-\left(-x\right)\right)=0
Subtract \frac{5}{3} from 2 to get \frac{1}{3}.
\frac{1}{3}+2x+2x^{2}-2\left(-1\right)x=0
Multiply 2 and -1 to get -2.
\frac{1}{3}+2x+2x^{2}+2x=0
Multiply -2 and -1 to get 2.
\frac{1}{3}+4x+2x^{2}=0
Combine 2x and 2x to get 4x.
2x^{2}+4x+\frac{1}{3}=0
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
x=\frac{-4±\sqrt{4^{2}-4\times 2\times \frac{1}{3}}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, 4 for b, and \frac{1}{3} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-4±\sqrt{16-4\times 2\times \frac{1}{3}}}{2\times 2}
Square 4.
x=\frac{-4±\sqrt{16-8\times \frac{1}{3}}}{2\times 2}
Multiply -4 times 2.
x=\frac{-4±\sqrt{16-\frac{8}{3}}}{2\times 2}
Multiply -8 times \frac{1}{3}.
x=\frac{-4±\sqrt{\frac{40}{3}}}{2\times 2}
Add 16 to -\frac{8}{3}.
x=\frac{-4±\frac{2\sqrt{30}}{3}}{2\times 2}
Take the square root of \frac{40}{3}.
x=\frac{-4±\frac{2\sqrt{30}}{3}}{4}
Multiply 2 times 2.
x=\frac{\frac{2\sqrt{30}}{3}-4}{4}
Now solve the equation x=\frac{-4±\frac{2\sqrt{30}}{3}}{4} when ± is plus. Add -4 to \frac{2\sqrt{30}}{3}.
x=\frac{\sqrt{30}}{6}-1
Divide -4+\frac{2\sqrt{30}}{3} by 4.
x=\frac{-\frac{2\sqrt{30}}{3}-4}{4}
Now solve the equation x=\frac{-4±\frac{2\sqrt{30}}{3}}{4} when ± is minus. Subtract \frac{2\sqrt{30}}{3} from -4.
x=-\frac{\sqrt{30}}{6}-1
Divide -4-\frac{2\sqrt{30}}{3} by 4.
x=\frac{\sqrt{30}}{6}-1 x=-\frac{\sqrt{30}}{6}-1
The equation is now solved.
1+2x+x^{2}+\left(4-\left(-x+3\right)\right)^{2}=\frac{5}{3}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(-1-x\right)^{2}.
1+2x+x^{2}+\left(4-\left(-x\right)-3\right)^{2}=\frac{5}{3}
To find the opposite of -x+3, find the opposite of each term.
1+2x+x^{2}+\left(1-\left(-x\right)\right)^{2}=\frac{5}{3}
Subtract 3 from 4 to get 1.
1+2x+x^{2}+1+2\left(-\left(-x\right)\right)+\left(-\left(-x\right)\right)^{2}=\frac{5}{3}
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(1-\left(-x\right)\right)^{2}.
1+2x+x^{2}+1+2\left(-\left(-x\right)\right)+\left(-x\right)^{2}=\frac{5}{3}
Calculate -\left(-x\right) to the power of 2 and get \left(-x\right)^{2}.
2+2x+x^{2}+2\left(-\left(-x\right)\right)+\left(-x\right)^{2}=\frac{5}{3}
Add 1 and 1 to get 2.
2+2x+x^{2}+2\left(-\left(-x\right)\right)+x^{2}=\frac{5}{3}
Calculate -x to the power of 2 and get x^{2}.
2+2x+2x^{2}+2\left(-\left(-x\right)\right)=\frac{5}{3}
Combine x^{2} and x^{2} to get 2x^{2}.
2x+2x^{2}+2\left(-\left(-x\right)\right)=\frac{5}{3}-2
Subtract 2 from both sides.
2x+2x^{2}+2\left(-\left(-x\right)\right)=-\frac{1}{3}
Subtract 2 from \frac{5}{3} to get -\frac{1}{3}.
2x+2x^{2}-2\left(-1\right)x=-\frac{1}{3}
Multiply 2 and -1 to get -2.
2x+2x^{2}+2x=-\frac{1}{3}
Multiply -2 and -1 to get 2.
4x+2x^{2}=-\frac{1}{3}
Combine 2x and 2x to get 4x.
2x^{2}+4x=-\frac{1}{3}
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
\frac{2x^{2}+4x}{2}=-\frac{\frac{1}{3}}{2}
Divide both sides by 2.
x^{2}+\frac{4}{2}x=-\frac{\frac{1}{3}}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}+2x=-\frac{\frac{1}{3}}{2}
Divide 4 by 2.
x^{2}+2x=-\frac{1}{6}
Divide -\frac{1}{3} by 2.
x^{2}+2x+1^{2}=-\frac{1}{6}+1^{2}
Divide 2, the coefficient of the x term, by 2 to get 1. Then add the square of 1 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+2x+1=-\frac{1}{6}+1
Square 1.
x^{2}+2x+1=\frac{5}{6}
Add -\frac{1}{6} to 1.
\left(x+1\right)^{2}=\frac{5}{6}
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{\frac{5}{6}}
Take the square root of both sides of the equation.
x+1=\frac{\sqrt{30}}{6} x+1=-\frac{\sqrt{30}}{6}
Simplify.
x=\frac{\sqrt{30}}{6}-1 x=-\frac{\sqrt{30}}{6}-1
Subtract 1 from both sides of the equation.
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}