Functions and Relations: Solving for f, g, and h

[nae99]

If f(x)= 2x+5, g(x)=0.5 and h(x)=3-1
find:
fg(x), gf(x), fh(3)


fg(x)
fg(x)= 2(0.5x)+5
fg(x)= x+5


gf(x)= 0.5(2x+5)
= x+2.5


fh(3)
fh (x) =2(3-1)+5
= 6-2+5
= 4+5


this last part of the question been puzzling me... could I get a little help pleasezz

 

[Dick]

If f(x)= 2x+5, g(x)=0.5 and h(x)=3-1
find:
fg(x), gf(x), fh(3)fg(x)
fg(x)= 2(0.5x)+5
fg(x)= x+5gf(x)= 0.5(2x+5)
= x+2.5fh(3)
fh (x) =2(3-1)+5
= 6-2+5
= 4+5 this last part of the question been puzzling me... could I get a little help pleasezz

I'm going to guess from your solution you meant g(x)=0.5*x. If you really meant h(x)=3-1 then the last one is fine. But writing h(x)=3-1 is a little odd. Why not just write h(x)=2, or is it another typo?

 

[eumyang]

If f(x)= 2x+5, g(x)=0.5 and h(x)=3-1
find:
fg(x), gf(x), fh(3)

Isn't the notation wrong? It looks like you want
(f \circ g)(x), (g \circ f)(x) and (f \circ h)(x)
(function composition)
but it looks more like
(fg)(x), (gf)(x) and (fh)(x)
(combining functions by multiplication)