If f(t) = sqrt(t(adsbygoogle = window.adsbygoogle || []).push({}); ^{2}- 16), find all values of t for which f(t) is a real number. Solve f(t) = 3.

All right, I know that I have to find values of t that would make the expression under the radical negative. I was trying to set up an equation to just get the domain.

t^{2}- 16 > 0

this would give me the domain, but it gets weird when i start working:

t^{2}> 16

t > + 4

but, if it's greater than +4 and -4, then it's just overlapping, and I know that isn't the answer. Actually the domain should be less than -4 and greater than 4 (also equal to those values).

I just don't know how you get the work to come out to that answer hehe... forgot something somewhere i guess.

thanks in advance for the help

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# Homework Help: Finding the domain.

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