Solve for x
x\in \left(-\infty,-3\right)\cup \left(3,\infty\right)
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x^{2}-9>0
Multiply the inequality by -1 to make the coefficient of the highest power in -x^{2}+9 positive. Since -1 is negative, the inequality direction is changed.
x^{2}>9
Add 9 to both sides.
x^{2}>3^{2}
Calculate the square root of 9 and get 3. Rewrite 9 as 3^{2}.
|x|>3
Inequality holds for |x|>3.
x<-3\text{; }x>3
Rewrite |x|>3 as x<-3\text{; }x>3.
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Limits
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