Solve for x (complex solution)
x=-\sqrt{2}i\approx -0-1.414213562i
x=\sqrt{2}i\approx 1.414213562i
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x^{2}=2-4
Subtract 4 from both sides.
x^{2}=-2
Subtract 4 from 2 to get -2.
x=\sqrt{2}i x=-\sqrt{2}i
The equation is now solved.
x^{2}+4-2=0
Subtract 2 from both sides.
x^{2}+2=0
Subtract 2 from 4 to get 2.
x=\frac{0±\sqrt{0^{2}-4\times 2}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and 2 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 2}}{2}
Square 0.
x=\frac{0±\sqrt{-8}}{2}
Multiply -4 times 2.
x=\frac{0±2\sqrt{2}i}{2}
Take the square root of -8.
x=\sqrt{2}i
Now solve the equation x=\frac{0±2\sqrt{2}i}{2} when ± is plus.
x=-\sqrt{2}i
Now solve the equation x=\frac{0±2\sqrt{2}i}{2} when ± is minus.
x=\sqrt{2}i x=-\sqrt{2}i
The equation is now solved.
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