Solve for x
x=-\frac{2}{3}\approx -0.666666667
x=-1
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\left(x-2\right)\left(x^{2}-2\right)+\left(x-1\right)\left(3x+2\right)=\left(x-2\right)\left(x-1\right)\left(x+2\right)-\left(x+2\right)\left(x+2\right)
Variable x cannot be equal to any of the values -2,1,2 since division by zero is not defined. Multiply both sides of the equation by \left(x-2\right)\left(x-1\right)\left(x+2\right), the least common multiple of x^{2}+x-2,x^{2}-4,x^{2}-3x+2.
\left(x-2\right)\left(x^{2}-2\right)+\left(x-1\right)\left(3x+2\right)=\left(x-2\right)\left(x-1\right)\left(x+2\right)-\left(x+2\right)^{2}
Multiply x+2 and x+2 to get \left(x+2\right)^{2}.
x^{3}-2x-2x^{2}+4+\left(x-1\right)\left(3x+2\right)=\left(x-2\right)\left(x-1\right)\left(x+2\right)-\left(x+2\right)^{2}
Use the distributive property to multiply x-2 by x^{2}-2.
x^{3}-2x-2x^{2}+4+3x^{2}-x-2=\left(x-2\right)\left(x-1\right)\left(x+2\right)-\left(x+2\right)^{2}
Use the distributive property to multiply x-1 by 3x+2 and combine like terms.
x^{3}-2x+x^{2}+4-x-2=\left(x-2\right)\left(x-1\right)\left(x+2\right)-\left(x+2\right)^{2}
Combine -2x^{2} and 3x^{2} to get x^{2}.
x^{3}-3x+x^{2}+4-2=\left(x-2\right)\left(x-1\right)\left(x+2\right)-\left(x+2\right)^{2}
Combine -2x and -x to get -3x.
x^{3}-3x+x^{2}+2=\left(x-2\right)\left(x-1\right)\left(x+2\right)-\left(x+2\right)^{2}
Subtract 2 from 4 to get 2.
x^{3}-3x+x^{2}+2=\left(x^{2}-3x+2\right)\left(x+2\right)-\left(x+2\right)^{2}
Use the distributive property to multiply x-2 by x-1 and combine like terms.
x^{3}-3x+x^{2}+2=x^{3}-x^{2}-4x+4-\left(x+2\right)^{2}
Use the distributive property to multiply x^{2}-3x+2 by x+2 and combine like terms.
x^{3}-3x+x^{2}+2=x^{3}-x^{2}-4x+4-\left(x^{2}+4x+4\right)
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(x+2\right)^{2}.
x^{3}-3x+x^{2}+2=x^{3}-x^{2}-4x+4-x^{2}-4x-4
To find the opposite of x^{2}+4x+4, find the opposite of each term.
x^{3}-3x+x^{2}+2=x^{3}-2x^{2}-4x+4-4x-4
Combine -x^{2} and -x^{2} to get -2x^{2}.
x^{3}-3x+x^{2}+2=x^{3}-2x^{2}-8x+4-4
Combine -4x and -4x to get -8x.
x^{3}-3x+x^{2}+2=x^{3}-2x^{2}-8x
Subtract 4 from 4 to get 0.
x^{3}-3x+x^{2}+2-x^{3}=-2x^{2}-8x
Subtract x^{3} from both sides.
-3x+x^{2}+2=-2x^{2}-8x
Combine x^{3} and -x^{3} to get 0.
-3x+x^{2}+2+2x^{2}=-8x
Add 2x^{2} to both sides.
-3x+3x^{2}+2=-8x
Combine x^{2} and 2x^{2} to get 3x^{2}.
-3x+3x^{2}+2+8x=0
Add 8x to both sides.
5x+3x^{2}+2=0
Combine -3x and 8x to get 5x.
3x^{2}+5x+2=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=5 ab=3\times 2=6
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as 3x^{2}+ax+bx+2. To find a and b, set up a system to be solved.
1,6 2,3
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. List all such integer pairs that give product 6.
1+6=7 2+3=5
Calculate the sum for each pair.
a=2 b=3
The solution is the pair that gives sum 5.
\left(3x^{2}+2x\right)+\left(3x+2\right)
Rewrite 3x^{2}+5x+2 as \left(3x^{2}+2x\right)+\left(3x+2\right).
x\left(3x+2\right)+3x+2
Factor out x in 3x^{2}+2x.
\left(3x+2\right)\left(x+1\right)
Factor out common term 3x+2 by using distributive property.
x=-\frac{2}{3} x=-1
To find equation solutions, solve 3x+2=0 and x+1=0.
\left(x-2\right)\left(x^{2}-2\right)+\left(x-1\right)\left(3x+2\right)=\left(x-2\right)\left(x-1\right)\left(x+2\right)-\left(x+2\right)\left(x+2\right)
Variable x cannot be equal to any of the values -2,1,2 since division by zero is not defined. Multiply both sides of the equation by \left(x-2\right)\left(x-1\right)\left(x+2\right), the least common multiple of x^{2}+x-2,x^{2}-4,x^{2}-3x+2.
\left(x-2\right)\left(x^{2}-2\right)+\left(x-1\right)\left(3x+2\right)=\left(x-2\right)\left(x-1\right)\left(x+2\right)-\left(x+2\right)^{2}
Multiply x+2 and x+2 to get \left(x+2\right)^{2}.
x^{3}-2x-2x^{2}+4+\left(x-1\right)\left(3x+2\right)=\left(x-2\right)\left(x-1\right)\left(x+2\right)-\left(x+2\right)^{2}
Use the distributive property to multiply x-2 by x^{2}-2.
x^{3}-2x-2x^{2}+4+3x^{2}-x-2=\left(x-2\right)\left(x-1\right)\left(x+2\right)-\left(x+2\right)^{2}
Use the distributive property to multiply x-1 by 3x+2 and combine like terms.
x^{3}-2x+x^{2}+4-x-2=\left(x-2\right)\left(x-1\right)\left(x+2\right)-\left(x+2\right)^{2}
Combine -2x^{2} and 3x^{2} to get x^{2}.
x^{3}-3x+x^{2}+4-2=\left(x-2\right)\left(x-1\right)\left(x+2\right)-\left(x+2\right)^{2}
Combine -2x and -x to get -3x.
x^{3}-3x+x^{2}+2=\left(x-2\right)\left(x-1\right)\left(x+2\right)-\left(x+2\right)^{2}
Subtract 2 from 4 to get 2.
x^{3}-3x+x^{2}+2=\left(x^{2}-3x+2\right)\left(x+2\right)-\left(x+2\right)^{2}
Use the distributive property to multiply x-2 by x-1 and combine like terms.
x^{3}-3x+x^{2}+2=x^{3}-x^{2}-4x+4-\left(x+2\right)^{2}
Use the distributive property to multiply x^{2}-3x+2 by x+2 and combine like terms.
x^{3}-3x+x^{2}+2=x^{3}-x^{2}-4x+4-\left(x^{2}+4x+4\right)
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(x+2\right)^{2}.
x^{3}-3x+x^{2}+2=x^{3}-x^{2}-4x+4-x^{2}-4x-4
To find the opposite of x^{2}+4x+4, find the opposite of each term.
x^{3}-3x+x^{2}+2=x^{3}-2x^{2}-4x+4-4x-4
Combine -x^{2} and -x^{2} to get -2x^{2}.
x^{3}-3x+x^{2}+2=x^{3}-2x^{2}-8x+4-4
Combine -4x and -4x to get -8x.
x^{3}-3x+x^{2}+2=x^{3}-2x^{2}-8x
Subtract 4 from 4 to get 0.
x^{3}-3x+x^{2}+2-x^{3}=-2x^{2}-8x
Subtract x^{3} from both sides.
-3x+x^{2}+2=-2x^{2}-8x
Combine x^{3} and -x^{3} to get 0.
-3x+x^{2}+2+2x^{2}=-8x
Add 2x^{2} to both sides.
-3x+3x^{2}+2=-8x
Combine x^{2} and 2x^{2} to get 3x^{2}.
-3x+3x^{2}+2+8x=0
Add 8x to both sides.
5x+3x^{2}+2=0
Combine -3x and 8x to get 5x.
3x^{2}+5x+2=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{-5±\sqrt{5^{2}-4\times 3\times 2}}{2\times 3}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 3 for a, 5 for b, and 2 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-5±\sqrt{25-4\times 3\times 2}}{2\times 3}
Square 5.
x=\frac{-5±\sqrt{25-12\times 2}}{2\times 3}
Multiply -4 times 3.
x=\frac{-5±\sqrt{25-24}}{2\times 3}
Multiply -12 times 2.
x=\frac{-5±\sqrt{1}}{2\times 3}
Add 25 to -24.
x=\frac{-5±1}{2\times 3}
Take the square root of 1.
x=\frac{-5±1}{6}
Multiply 2 times 3.
x=-\frac{4}{6}
Now solve the equation x=\frac{-5±1}{6} when ± is plus. Add -5 to 1.
x=-\frac{2}{3}
Reduce the fraction \frac{-4}{6} to lowest terms by extracting and canceling out 2.
x=-\frac{6}{6}
Now solve the equation x=\frac{-5±1}{6} when ± is minus. Subtract 1 from -5.
x=-1
Divide -6 by 6.
x=-\frac{2}{3} x=-1
The equation is now solved.
\left(x-2\right)\left(x^{2}-2\right)+\left(x-1\right)\left(3x+2\right)=\left(x-2\right)\left(x-1\right)\left(x+2\right)-\left(x+2\right)\left(x+2\right)
Variable x cannot be equal to any of the values -2,1,2 since division by zero is not defined. Multiply both sides of the equation by \left(x-2\right)\left(x-1\right)\left(x+2\right), the least common multiple of x^{2}+x-2,x^{2}-4,x^{2}-3x+2.
\left(x-2\right)\left(x^{2}-2\right)+\left(x-1\right)\left(3x+2\right)=\left(x-2\right)\left(x-1\right)\left(x+2\right)-\left(x+2\right)^{2}
Multiply x+2 and x+2 to get \left(x+2\right)^{2}.
x^{3}-2x-2x^{2}+4+\left(x-1\right)\left(3x+2\right)=\left(x-2\right)\left(x-1\right)\left(x+2\right)-\left(x+2\right)^{2}
Use the distributive property to multiply x-2 by x^{2}-2.
x^{3}-2x-2x^{2}+4+3x^{2}-x-2=\left(x-2\right)\left(x-1\right)\left(x+2\right)-\left(x+2\right)^{2}
Use the distributive property to multiply x-1 by 3x+2 and combine like terms.
x^{3}-2x+x^{2}+4-x-2=\left(x-2\right)\left(x-1\right)\left(x+2\right)-\left(x+2\right)^{2}
Combine -2x^{2} and 3x^{2} to get x^{2}.
x^{3}-3x+x^{2}+4-2=\left(x-2\right)\left(x-1\right)\left(x+2\right)-\left(x+2\right)^{2}
Combine -2x and -x to get -3x.
x^{3}-3x+x^{2}+2=\left(x-2\right)\left(x-1\right)\left(x+2\right)-\left(x+2\right)^{2}
Subtract 2 from 4 to get 2.
x^{3}-3x+x^{2}+2=\left(x^{2}-3x+2\right)\left(x+2\right)-\left(x+2\right)^{2}
Use the distributive property to multiply x-2 by x-1 and combine like terms.
x^{3}-3x+x^{2}+2=x^{3}-x^{2}-4x+4-\left(x+2\right)^{2}
Use the distributive property to multiply x^{2}-3x+2 by x+2 and combine like terms.
x^{3}-3x+x^{2}+2=x^{3}-x^{2}-4x+4-\left(x^{2}+4x+4\right)
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(x+2\right)^{2}.
x^{3}-3x+x^{2}+2=x^{3}-x^{2}-4x+4-x^{2}-4x-4
To find the opposite of x^{2}+4x+4, find the opposite of each term.
x^{3}-3x+x^{2}+2=x^{3}-2x^{2}-4x+4-4x-4
Combine -x^{2} and -x^{2} to get -2x^{2}.
x^{3}-3x+x^{2}+2=x^{3}-2x^{2}-8x+4-4
Combine -4x and -4x to get -8x.
x^{3}-3x+x^{2}+2=x^{3}-2x^{2}-8x
Subtract 4 from 4 to get 0.
x^{3}-3x+x^{2}+2-x^{3}=-2x^{2}-8x
Subtract x^{3} from both sides.
-3x+x^{2}+2=-2x^{2}-8x
Combine x^{3} and -x^{3} to get 0.
-3x+x^{2}+2+2x^{2}=-8x
Add 2x^{2} to both sides.
-3x+3x^{2}+2=-8x
Combine x^{2} and 2x^{2} to get 3x^{2}.
-3x+3x^{2}+2+8x=0
Add 8x to both sides.
5x+3x^{2}+2=0
Combine -3x and 8x to get 5x.
5x+3x^{2}=-2
Subtract 2 from both sides. Anything subtracted from zero gives its negation.
3x^{2}+5x=-2
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{3x^{2}+5x}{3}=-\frac{2}{3}
Divide both sides by 3.
x^{2}+\frac{5}{3}x=-\frac{2}{3}
Dividing by 3 undoes the multiplication by 3.
x^{2}+\frac{5}{3}x+\left(\frac{5}{6}\right)^{2}=-\frac{2}{3}+\left(\frac{5}{6}\right)^{2}
Divide \frac{5}{3}, the coefficient of the x term, by 2 to get \frac{5}{6}. Then add the square of \frac{5}{6} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{5}{3}x+\frac{25}{36}=-\frac{2}{3}+\frac{25}{36}
Square \frac{5}{6} by squaring both the numerator and the denominator of the fraction.
x^{2}+\frac{5}{3}x+\frac{25}{36}=\frac{1}{36}
Add -\frac{2}{3} to \frac{25}{36} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x+\frac{5}{6}\right)^{2}=\frac{1}{36}
Factor x^{2}+\frac{5}{3}x+\frac{25}{36}. 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+\frac{5}{6}\right)^{2}}=\sqrt{\frac{1}{36}}
Take the square root of both sides of the equation.
x+\frac{5}{6}=\frac{1}{6} x+\frac{5}{6}=-\frac{1}{6}
Simplify.
x=-\frac{2}{3} x=-1
Subtract \frac{5}{6} 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}