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Katherine2007
Aug 1, 2007, 08:23 AM
If f(x)= x^4 +7 and g(x) = x+5 and h(x) =x^1/2
then what does

f o g o h (x) =??

Capuchin
Aug 1, 2007, 08:46 AM
what is the o meant to represent?

you mean f(g(h(x))) ?

Katherine2007
Aug 1, 2007, 09:08 AM
what is the o meant to represent?

you mean f(g(h(x))) ?
Yes.

Capuchin
Aug 1, 2007, 09:19 AM
okay so that means you need to put h(x) as x into g(x), and then put that result (g(h(x))) as x into f(x).

for example if m(x) = 1+x and n(x) = x+2 then m(n(x)) is putting n(x) as x into m(x) so it's 1+(n(x)) = 1+(x+2) = 3+x

now can you do yours?

Katherine2007
Aug 1, 2007, 09:27 AM
okay so that means you need to put h(x) as x into g(x), and then put that result (g(h(x))) as x into f(x).

for example if m(x) = 1+x and n(x) = x+2 then m(n(x)) is putting n(x) as x into m(x) so it's 1+(n(x)) = 1+(x+2) = 3+x

now can you do yours?
so then

x^1/2 + 5 then becomes the (x) that you plug into f(x)= x^4 +7


?

just to double check x^1/2 is the same as the sqrt of x right?

Capuchin
Aug 1, 2007, 09:30 AM
Yup and yup.

Katherine2007
Aug 1, 2007, 09:37 AM
so then

x^1/2 + 5 then becomes the (x) that you plug into f(x)= x^4 +7


??

just to double check x^1/2 is the same as the sqrt of x right?
thanks, I got the right answer now! The computer was throwing me off a bit because it wouldn't recognize x^1/2... I had to enter it as x^.5... but your example really helped! I've never had calculus or pre-calculus and the last math I had was 5 years ago!