# Thread: Operations of square root functions

1. ## Operations of square root functions

I can't remember square root rules and I'm looking for

f+g, f-g, fxg, f/g

f(x)=sqrt(1+x)
g(x)=sqrt(1-x)

2. Originally Posted by sharpiemarker
I can't remember square root rules and I'm looking for

f+g, f-g, fxg, f/g

f(x)=sqrt(1+x)
g(x)=sqrt(1-x)
There are no simple rules for adding / subtracting square roots, but you do have:

$\displaystyle \sqrt a \sqrt b = \sqrt {ab}, \frac {\sqrt a} {\sqrt b} = \sqrt {\frac a b}$. That may help a little.

3. Originally Posted by Matt Westwood
There are no simple rules for adding / subtracting square roots, but you do have:

$\displaystyle \sqrt a \sqrt b = \sqrt {ab}, \frac {\sqrt a} {\sqrt b} = \sqrt {\frac a b}$. That may help a little.
That does help. Any suggestions for the addition and subtraction of the functions? Thanks!

4. Originally Posted by sharpiemarker
That does help. Any suggestions for the addition and subtraction of the functions? Thanks!
(shrug) $\displaystyle f(x) + g(x) = \sqrt{1+x} + \sqrt{1-x}$ and similar for the subtract one is probably as best as you can do.

Unless there's something embarrassingly basic that I've completely forgotten.

5. Originally Posted by Matt Westwood
(shrug) $\displaystyle f(x) + g(x) = \sqrt{1+x} + \sqrt{1-x}$ and similar for the subtract one is probably as best as you can do.

Unless there's something embarrassingly basic that I've completely forgotten.
Hehe, I see we're on the same page then. It seems like I should simplify that but I'm not seeing how. Thanks for the suggestions.

6. Originally Posted by sharpiemarker
Hehe, I see we're on the same page then. It seems like I should simplify that but I'm not seeing how. Thanks for the suggestions.
It does not simplify any further (Matt was joking - he's forgotten nothing).