Solve for n
n=3
n=-3
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2n^{2}=9\times 2
Multiply both sides by 2.
n^{2}=9
Cancel out 2 on both sides.
n^{2}-9=0
Subtract 9 from both sides.
\left(n-3\right)\left(n+3\right)=0
Consider n^{2}-9. Rewrite n^{2}-9 as n^{2}-3^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
n=3 n=-3
To find equation solutions, solve n-3=0 and n+3=0.
2n^{2}=9\times 2
Multiply both sides by 2.
n^{2}=9
Cancel out 2 on both sides.
n=3 n=-3
Take the square root of both sides of the equation.
2n^{2}=9\times 2
Multiply both sides by 2.
n^{2}=9
Cancel out 2 on both sides.
n^{2}-9=0
Subtract 9 from both sides.
n=\frac{0±\sqrt{0^{2}-4\left(-9\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and -9 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
n=\frac{0±\sqrt{-4\left(-9\right)}}{2}
Square 0.
n=\frac{0±\sqrt{36}}{2}
Multiply -4 times -9.
n=\frac{0±6}{2}
Take the square root of 36.
n=3
Now solve the equation n=\frac{0±6}{2} when ± is plus. Divide 6 by 2.
n=-3
Now solve the equation n=\frac{0±6}{2} when ± is minus. Divide -6 by 2.
n=3 n=-3
The equation is now solved.
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Limits
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