Solve for x
x = \frac{\sqrt{14}}{2} \approx 1.870828693
x = -\frac{\sqrt{14}}{2} \approx -1.870828693
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-2x^{2}-5x+3+5x+4=0
Combine -6x and x to get -5x.
-2x^{2}+3+4=0
Combine -5x and 5x to get 0.
-2x^{2}+7=0
Add 3 and 4 to get 7.
-2x^{2}=-7
Subtract 7 from both sides. Anything subtracted from zero gives its negation.
x^{2}=\frac{-7}{-2}
Divide both sides by -2.
x^{2}=\frac{7}{2}
Fraction \frac{-7}{-2} can be simplified to \frac{7}{2} by removing the negative sign from both the numerator and the denominator.
x=\frac{\sqrt{14}}{2} x=-\frac{\sqrt{14}}{2}
Take the square root of both sides of the equation.
-2x^{2}-5x+3+5x+4=0
Combine -6x and x to get -5x.
-2x^{2}+3+4=0
Combine -5x and 5x to get 0.
-2x^{2}+7=0
Add 3 and 4 to get 7.
x=\frac{0±\sqrt{0^{2}-4\left(-2\right)\times 7}}{2\left(-2\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -2 for a, 0 for b, and 7 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-2\right)\times 7}}{2\left(-2\right)}
Square 0.
x=\frac{0±\sqrt{8\times 7}}{2\left(-2\right)}
Multiply -4 times -2.
x=\frac{0±\sqrt{56}}{2\left(-2\right)}
Multiply 8 times 7.
x=\frac{0±2\sqrt{14}}{2\left(-2\right)}
Take the square root of 56.
x=\frac{0±2\sqrt{14}}{-4}
Multiply 2 times -2.
x=-\frac{\sqrt{14}}{2}
Now solve the equation x=\frac{0±2\sqrt{14}}{-4} when ± is plus.
x=\frac{\sqrt{14}}{2}
Now solve the equation x=\frac{0±2\sqrt{14}}{-4} when ± is minus.
x=-\frac{\sqrt{14}}{2} x=\frac{\sqrt{14}}{2}
The equation is now solved.
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Matrix
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Simultaneous equation
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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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