Thread: functions and domains

Let f(x)=square root (1+x) and g(x)=square root (1-x) Find f+g, f-g, fg, f/g and their domains.

I know that to add these functions, I have to add sqrt (1+x) and sqrt (1-x) but I'm unclear how to add square roots and I'm not sure how to find the domains.

Originally Posted by sjenkins

Let f(x)=square root (1+x) and g(x)=square root (1-x) Find f+g, f-g, fg, f/g and their domains.

I know that to add these functions, I have to add sqrt (1+x) and sqrt (1-x) but I'm unclear how to add square roots and I'm not sure how to find the domains.

Domain of is .
Domain of is .

Thus, domain of is die intersection i.e.

While domain of is minus since denominator is zero.
This gives us .