# Thread: Square Rooting Both Sides of the Equality

1. ## Square Rooting Both Sides of the Equality

Hey

When you are square rooting both sides of the equality, why do you have to apply plus or minus?

x^2 = 4
x = + or - sqrt(4)

NOTE: I reinstalled windows and couldn't use MathType to generate TEX.

Sam

2. ## Re: Square Rooting Both Sides of the Equality

Originally Posted by ArcherSam
Hey

When you are square rooting both sides of the equality, why do you have to apply plus or minus?

x^2 = 4
x = + or - sqrt(4)

NOTE: I reinstalled windows and couldn't use MathType to generate TEX.

Sam
Because $(-x)^2 = (-x) \cdot (-x) = x^2$

By the way $\sqrt{4} = 2$

For tex wrap your equation with $$...$$ where ... represents your equation. For example my first line is $$(-x)^2 = (-x) \cdot (-x) = x^2$$

You can also quote someone else's post and see what they've done

3. ## Re: Square Rooting Both Sides of the Equality

@e^(i*pi)

Okay, because even powers can input negative and postive values, you include the plus and minus to account for this property. I see!

Sam

4. ## Re: Square Rooting Both Sides of the Equality

Originally Posted by ArcherSam
@e^(i*pi)

Okay, because even powers can input negative and postive values, you include the plus and minus to account for this property. I see!

Sam
That's it