Solve for x (complex solution)
x=-i
x=i
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-4x^{2}-3=1
Swap sides so that all variable terms are on the left hand side.
-4x^{2}=1+3
Add 3 to both sides.
-4x^{2}=4
Add 1 and 3 to get 4.
x^{2}=\frac{4}{-4}
Divide both sides by -4.
x^{2}=-1
Divide 4 by -4 to get -1.
x=i x=-i
The equation is now solved.
-4x^{2}-3=1
Swap sides so that all variable terms are on the left hand side.
-4x^{2}-3-1=0
Subtract 1 from both sides.
-4x^{2}-4=0
Subtract 1 from -3 to get -4.
x=\frac{0±\sqrt{0^{2}-4\left(-4\right)\left(-4\right)}}{2\left(-4\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -4 for a, 0 for b, and -4 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-4\right)\left(-4\right)}}{2\left(-4\right)}
Square 0.
x=\frac{0±\sqrt{16\left(-4\right)}}{2\left(-4\right)}
Multiply -4 times -4.
x=\frac{0±\sqrt{-64}}{2\left(-4\right)}
Multiply 16 times -4.
x=\frac{0±8i}{2\left(-4\right)}
Take the square root of -64.
x=\frac{0±8i}{-8}
Multiply 2 times -4.
x=-i
Now solve the equation x=\frac{0±8i}{-8} when ± is plus.
x=i
Now solve the equation x=\frac{0±8i}{-8} when ± is minus.
x=-i x=i
The equation is now solved.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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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}