Question

How to do composition of functions?

Answer 1

could you give a question as an example

Answer 2

der you go

Answer 3

okay so you have
f(x)=2x-1
g(x)=x+2

so you want
gf

this means you will do g(f)

so your g function is
g(x)=x+2
now g(f)=f+2
because it replaces all the x's

but you know that f(x)=2x-1

so you are doing g(f) which is equal to g(2x-1)

so your g function is
g(x)=x+2

instead of x you will replace all x's with 2x-1

so g(2x-1)=2x-1+2
g(2x-1)=2x+1

Answer 4

So composition is just multiplying??

Answer 5

no
you had gf
that is a function of f
but you know that f is 2x-1
so you sub that into your function for g

you are replacing the function on the right with its function of x
then the substituting it into the function that follows the one on the right

like here
the function the right is f which is 2x-1
you subbed that into the function for g

Answer 6

So composition is putting f into g?

Answer 7

yes

Answer 8

Oh.. okay. Thanks \(\huge\ddot\smile\)

Answer 9

if it makes it easier to understand
try this

you have
gf

you could re write it to be
gf(x)

you know f(x)=2x-1
so you can rewrite it to be
g(2x-1)

sub it into the g function