Solve for x (complex solution)
x=-\frac{\sqrt{3}i}{2}\approx -0-0.866025404i
x=\frac{\sqrt{3}i}{2}\approx 0.866025404i
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8x^{2}=-6
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
8x^{2}-\left(-6\right)=-6-\left(-6\right)
Add 6 to both sides of the equation.
8x^{2}-\left(-6\right)=0
Subtracting -6 from itself leaves 0.
8x^{2}+6=0
Subtract -6 from 0.
x=\frac{0±\sqrt{0^{2}-4\times 8\times 6}}{2\times 8}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 8 for a, 0 for b, and 6 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 8\times 6}}{2\times 8}
Square 0.
x=\frac{0±\sqrt{-32\times 6}}{2\times 8}
Multiply -4 times 8.
x=\frac{0±\sqrt{-192}}{2\times 8}
Multiply -32 times 6.
x=\frac{0±8\sqrt{3}i}{2\times 8}
Take the square root of -192.
x=\frac{0±8\sqrt{3}i}{16}
Multiply 2 times 8.
x=\frac{\sqrt{3}i}{2}
Now solve the equation x=\frac{0±8\sqrt{3}i}{16} when ± is plus.
x=-\frac{\sqrt{3}i}{2}
Now solve the equation x=\frac{0±8\sqrt{3}i}{16} when ± is minus.
x=\frac{\sqrt{3}i}{2} x=-\frac{\sqrt{3}i}{2}
The equation is now solved.
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Limits
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