Solve sqrt{x-1}=u

$$\sqrt { x - 1 } = u$$

Solve for x

$$x=u^{2}+1$$

$$u\geq 0$$

Steps for Solving Radical Equations

Square both sides of the equation.

$$x-1=u^{2}$$

Add 1 to both sides of the equation.

$$x-1-\left(-1\right)=u^{2}-\left(-1\right)$$

Subtracting -1 from itself leaves 0.

$$x=u^{2}-\left(-1\right)$$

Subtract -1 from u^{2}.

$$x=u^{2}+1$$

Solve for u (complex solution)

$$u=\sqrt{x-1}$$

Solve for x (complex solution)

$$x=u^{2}+1$$

$$arg(u)<\pi \text{ or }u=0$$

Solve for u

$$u=\sqrt{x-1}$$

$$x\geq 1$$