Solve for x
x=3
x=-3
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8x+4+\left(x^{2}-x+1\right)\times 4-\left(x+1\right)\left(5x-1\right)=0
Variable x cannot be equal to -1 since division by zero is not defined. Multiply both sides of the equation by \left(x+1\right)\left(x^{2}-x+1\right), the least common multiple of x^{3}+1,x+1,x^{2}-x+1.
8x+4+4x^{2}-4x+4-\left(x+1\right)\left(5x-1\right)=0
Use the distributive property to multiply x^{2}-x+1 by 4.
4x+4+4x^{2}+4-\left(x+1\right)\left(5x-1\right)=0
Combine 8x and -4x to get 4x.
4x+8+4x^{2}-\left(x+1\right)\left(5x-1\right)=0
Add 4 and 4 to get 8.
4x+8+4x^{2}-\left(5x^{2}+4x-1\right)=0
Use the distributive property to multiply x+1 by 5x-1 and combine like terms.
4x+8+4x^{2}-5x^{2}-4x+1=0
To find the opposite of 5x^{2}+4x-1, find the opposite of each term.
4x+8-x^{2}-4x+1=0
Combine 4x^{2} and -5x^{2} to get -x^{2}.
8-x^{2}+1=0
Combine 4x and -4x to get 0.
9-x^{2}=0
Add 8 and 1 to get 9.
-x^{2}=-9
Subtract 9 from both sides. Anything subtracted from zero gives its negation.
x^{2}=\frac{-9}{-1}
Divide both sides by -1.
x^{2}=9
Fraction \frac{-9}{-1} can be simplified to 9 by removing the negative sign from both the numerator and the denominator.
x=3 x=-3
Take the square root of both sides of the equation.
8x+4+\left(x^{2}-x+1\right)\times 4-\left(x+1\right)\left(5x-1\right)=0
Variable x cannot be equal to -1 since division by zero is not defined. Multiply both sides of the equation by \left(x+1\right)\left(x^{2}-x+1\right), the least common multiple of x^{3}+1,x+1,x^{2}-x+1.
8x+4+4x^{2}-4x+4-\left(x+1\right)\left(5x-1\right)=0
Use the distributive property to multiply x^{2}-x+1 by 4.
4x+4+4x^{2}+4-\left(x+1\right)\left(5x-1\right)=0
Combine 8x and -4x to get 4x.
4x+8+4x^{2}-\left(x+1\right)\left(5x-1\right)=0
Add 4 and 4 to get 8.
4x+8+4x^{2}-\left(5x^{2}+4x-1\right)=0
Use the distributive property to multiply x+1 by 5x-1 and combine like terms.
4x+8+4x^{2}-5x^{2}-4x+1=0
To find the opposite of 5x^{2}+4x-1, find the opposite of each term.
4x+8-x^{2}-4x+1=0
Combine 4x^{2} and -5x^{2} to get -x^{2}.
8-x^{2}+1=0
Combine 4x and -4x to get 0.
9-x^{2}=0
Add 8 and 1 to get 9.
-x^{2}+9=0
Quadratic equations like this one, with an x^{2} term but no x term, can still be solved using the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}, once they are put in standard form: ax^{2}+bx+c=0.
x=\frac{0±\sqrt{0^{2}-4\left(-1\right)\times 9}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 0 for b, and 9 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-1\right)\times 9}}{2\left(-1\right)}
Square 0.
x=\frac{0±\sqrt{4\times 9}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{0±\sqrt{36}}{2\left(-1\right)}
Multiply 4 times 9.
x=\frac{0±6}{2\left(-1\right)}
Take the square root of 36.
x=\frac{0±6}{-2}
Multiply 2 times -1.
x=-3
Now solve the equation x=\frac{0±6}{-2} when ± is plus. Divide 6 by -2.
x=3
Now solve the equation x=\frac{0±6}{-2} when ± is minus. Divide -6 by -2.
x=-3 x=3
The equation is now solved.
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Matrix
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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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