Solve for x
x = \frac{1}{2} = 0.5
x=2
Solve for t (complex solution)
t\in \mathrm{C}
x=\frac{1}{2}\text{ or }x=2
Solve for t
t\in \mathrm{R}
x=\frac{1}{2}\text{ or }x=2
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2x^{2}-5x+2=0
Anything times zero gives zero.
a+b=-5 ab=2\times 2=4
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as 2x^{2}+ax+bx+2. To find a and b, set up a system to be solved.
-1,-4 -2,-2
Since ab is positive, a and b have the same sign. Since a+b is negative, a and b are both negative. List all such integer pairs that give product 4.
-1-4=-5 -2-2=-4
Calculate the sum for each pair.
a=-4 b=-1
The solution is the pair that gives sum -5.
\left(2x^{2}-4x\right)+\left(-x+2\right)
Rewrite 2x^{2}-5x+2 as \left(2x^{2}-4x\right)+\left(-x+2\right).
2x\left(x-2\right)-\left(x-2\right)
Factor out 2x in the first and -1 in the second group.
\left(x-2\right)\left(2x-1\right)
Factor out common term x-2 by using distributive property.
x=2 x=\frac{1}{2}
To find equation solutions, solve x-2=0 and 2x-1=0.
2x^{2}-5x+2=0
Anything times zero gives zero.
x=\frac{-\left(-5\right)±\sqrt{\left(-5\right)^{2}-4\times 2\times 2}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, -5 for b, and 2 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-5\right)±\sqrt{25-4\times 2\times 2}}{2\times 2}
Square -5.
x=\frac{-\left(-5\right)±\sqrt{25-8\times 2}}{2\times 2}
Multiply -4 times 2.
x=\frac{-\left(-5\right)±\sqrt{25-16}}{2\times 2}
Multiply -8 times 2.
x=\frac{-\left(-5\right)±\sqrt{9}}{2\times 2}
Add 25 to -16.
x=\frac{-\left(-5\right)±3}{2\times 2}
Take the square root of 9.
x=\frac{5±3}{2\times 2}
The opposite of -5 is 5.
x=\frac{5±3}{4}
Multiply 2 times 2.
x=\frac{8}{4}
Now solve the equation x=\frac{5±3}{4} when ± is plus. Add 5 to 3.
x=2
Divide 8 by 4.
x=\frac{2}{4}
Now solve the equation x=\frac{5±3}{4} when ± is minus. Subtract 3 from 5.
x=\frac{1}{2}
Reduce the fraction \frac{2}{4} to lowest terms by extracting and canceling out 2.
x=2 x=\frac{1}{2}
The equation is now solved.
2x^{2}-5x+2=0
Anything times zero gives zero.
2x^{2}-5x=-2
Subtract 2 from both sides. Anything subtracted from zero gives its negation.
\frac{2x^{2}-5x}{2}=-\frac{2}{2}
Divide both sides by 2.
x^{2}-\frac{5}{2}x=-\frac{2}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}-\frac{5}{2}x=-1
Divide -2 by 2.
x^{2}-\frac{5}{2}x+\left(-\frac{5}{4}\right)^{2}=-1+\left(-\frac{5}{4}\right)^{2}
Divide -\frac{5}{2}, the coefficient of the x term, by 2 to get -\frac{5}{4}. Then add the square of -\frac{5}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{5}{2}x+\frac{25}{16}=-1+\frac{25}{16}
Square -\frac{5}{4} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{5}{2}x+\frac{25}{16}=\frac{9}{16}
Add -1 to \frac{25}{16}.
\left(x-\frac{5}{4}\right)^{2}=\frac{9}{16}
Factor x^{2}-\frac{5}{2}x+\frac{25}{16}. 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}{4}\right)^{2}}=\sqrt{\frac{9}{16}}
Take the square root of both sides of the equation.
x-\frac{5}{4}=\frac{3}{4} x-\frac{5}{4}=-\frac{3}{4}
Simplify.
x=2 x=\frac{1}{2}
Add \frac{5}{4} to 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}