let f(x)=x+3 and let g(x)=6x-9?

1 ⤊

find the function (f . g)(3) (the dot indicates multiplying f and g

2007-09-08 09:35:57 · 3 answers · asked by Nanna2 1 in Science & Mathematics ➔ Mathematics

f ( g (x) )
= f (6x - 9)
= 6x - 9 + 3
= 6x - 6
= 6 (x - 1)

f ( g (3) )
= 6 (3 - 1)
= 12

2007-09-12 06:45:36 · answer #1 · answered by Como 7 · 1⤊ 0⤋

f(3) = 3+3 = 6

g(3) = (3.6) -9 = 18-9 = 9

so, because the multiplication of functions is commutative, (f.g)(3) = 6.9 = 54

So your answer is 54

2007-09-08 10:37:48 · answer #2 · answered by Anonymous · 0⤊ 0⤋

1.Find the f(x) and g(x)
f(x)=-3, g(x)=1.5

2. Multiply (3x1.5)(3)

3. = 13.5

*SORRY, I completely forgot to substitute it back in. Sorry again..

2007-09-08 09:46:20 · answer #3 · answered by ? 3 · 0⤊ 1⤋