Precalculus Examples

$\sqrt{\sqrt{81 x^{4}}}$

Step 1

Rewrite $81 x^{4}$ as ${(9 x^{2})}^{2}$ .

$\sqrt{\sqrt{{(9 x^{2})}^{2}}}$

Step 2

Pull terms out from under the radical, assuming positive real numbers.

$\sqrt{9 x^{2}}$

Step 3

Rewrite $9 x^{2}$ as ${(3 x)}^{2}$ .

$\sqrt{{(3 x)}^{2}}$

Step 4

Pull terms out from under the radical, assuming positive real numbers.

$3 x$