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2xx^{2}-2x\times 4=\left(x-2\right)\left(x+2\right)
Variable x cannot be equal to any of the values 0,2 since division by zero is not defined. Multiply both sides of the equation by 2x\left(x-2\right), the least common multiple of x-2,2-x,2x.
2x^{3}-2x\times 4=\left(x-2\right)\left(x+2\right)
To multiply powers of the same base, add their exponents. Add 1 and 2 to get 3.
2x^{3}-8x=\left(x-2\right)\left(x+2\right)
Multiply -2 and 4 to get -8.
2x^{3}-8x=x^{2}-4
Consider \left(x-2\right)\left(x+2\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 2.
2x^{3}-8x-x^{2}=-4
Subtract x^{2} from both sides.
2x^{3}-8x-x^{2}+4=0
Add 4 to both sides.
2x^{3}-x^{2}-8x+4=0
Rearrange the equation to put it in standard form. Place the terms in order from highest to lowest power.
±2,±4,±1,±\frac{1}{2}
By Rational Root Theorem, all rational roots of a polynomial are in the form \frac{p}{q}, where p divides the constant term 4 and q divides the leading coefficient 2. List all candidates \frac{p}{q}.
x=2
Find one such root by trying out all the integer values, starting from the smallest by absolute value. If no integer roots are found, try out fractions.
2x^{2}+3x-2=0
By Factor theorem, x-k is a factor of the polynomial for each root k. Divide 2x^{3}-x^{2}-8x+4 by x-2 to get 2x^{2}+3x-2. Solve the equation where the result equals to 0.
x=\frac{-3±\sqrt{3^{2}-4\times 2\left(-2\right)}}{2\times 2}
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. Substitute 2 for a, 3 for b, and -2 for c in the quadratic formula.
x=\frac{-3±5}{4}
Do the calculations.
x=-2 x=\frac{1}{2}
Solve the equation 2x^{2}+3x-2=0 when ± is plus and when ± is minus.
x=-2\text{ or }x=\frac{1}{2}
Remove the values that the variable cannot be equal to.
x=2 x=-2 x=\frac{1}{2}
List all found solutions.
x=\frac{1}{2} x=-2
Variable x cannot be equal to 2.