for the given function f and g . find the requested composite function value.
f(x)=sqrt (x+1)
g(x)= 3x
find (f o g)(1)
please give me the answer..

Question

anonymous · Answer

i have f((g(1))= square root  (3+1)
                    = square root (4)
                     =$$\pm2$$
is it right???

hero · Answer

I didn't see the square root.....

wait.....

Yes it is the sqrt (3x+1)
f(g(1)) = sqrt (4) = 2

anonymous · Answer

$$ the answer is \pm 2 or the answer is +2... i dont know which one is \right??$$

anonymous · Answer

thanks:)..

anonymous · Answer

i got my answer is +/- 2 but my teacher  said it's just +2... not -2

hero · Answer

Oh yeah, you can't take the sqrt of a negative number

hero · Answer

I retract my previous statement

hero · Answer

Sorry for the confusion, it's early morning here for me

anonymous · Answer

but (-2)^2= 4 too.

hero · Answer

That's true, but, hmmm. How can I explain this....

hero · Answer

There's a difference between squaring and taking a square root.

anonymous · Answer

so i dont know which one is the xactly answer +/- 2 or +2...???

hero · Answer

You can square two opposite numbers and get the same number, but you can only square root a positive number

hero · Answer

It's definitely +2 for the answer you seek.

hero · Answer

Once again, you cannot square root a negative number.....It's a mathematical law

anonymous · Answer

ok... thanks for helping :)

hero · Answer

You're welcome