functions: f(x) = 3 sqrt of x, g(x) = 3x. Find f*g, g*g, etc

[bailey07]

f(x) =3sqrt of x & g(x)=3x

A) (f*g) (4) =3(4) =12 3sqrt of 12
B) (g*g) (2) = 3sqrt of 2...3(3sqrt 2) = 9sqrt of 2
C) (f*f) (1) =3sqrt1 =3 =3sqrt of 3
D) (g*g)(0) =3(0) =0 3 sqrt of 0 =0



the * doesnt mean times, its the little dot symbol

 

[tkhunny]

Re: functions

f(x) =3sqrt of x & g(x)=3x

A) (f*g) (4) =3(4) =12 3sqrt of 12

I'm guessing someone wants 6sqrt(3). How will you get that?

B) (g*g) (2) = 3sqrt of 2...3(3sqrt 2) = 9sqrt of 2

This is just g(x). How did the square roots get in there?

C) (f*f) (1) =3sqrt1 =3 =3sqrt of 3

Right.

D) (g*g)(0) =3(0) =0 3 sqrt of 0 =0

Again with the square roots. Don't do that. g(x) doesn't change to f(x) because you use it once.

g(g(g(g(g(x))))) = something with no square roots. The square roots are in f(x).

 

[bailey07]

for part b i meant to put (g*f)(2)...so i think my answer might be right...i know c&d are right but i still don't think a is