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

AI Thread Summary
The discussion focuses on finding the values of function compositions and products for f(x) = 2x + 5, g(x) = 0.5, and h(x) = 3 - 1. The calculations yield fg(x) = x + 5, gf(x) = x + 2.5, and fh(3) = 8. Participants clarify that the notation used may be confusing, as it appears to mix function composition with multiplication. There is also a suggestion to simplify h(x) for clarity. Overall, the thread emphasizes the importance of proper notation in mathematical expressions.
nae99
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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 :confused:
 
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nae99 said:
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 :confused:

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?
 
Last edited:
nae99 said:
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)
 
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