Solve for u u^2=4

$u^{2} = 4$

Take the square root of both sides of the equation to eliminate the exponent on the left side.

$u = \pm \sqrt{4}$

Simplify $\pm \sqrt{4}$ .

Rewrite $4$ as $2^{2}$ .

$u = \pm \sqrt{2^{2}}$

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

$u = \pm 2$

The complete solution is the result of both the positive and negative portions of the solution.

First, use the positive value of the $\pm$ to find the first solution.

$u = 2$

Next, use the negative value of the $\pm$ to find the second solution.

$u = - 2$

The complete solution is the result of both the positive and negative portions of the solution.

$u = 2, - 2$