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phoenirius
Jan 24, 2006, 02:50 PM
Knowing f(x)=x^2+x and g(x)=2x+1 how would you solve f(g(x)) and
(g (circle) f)(4)??

How do you determine the f^(-1) of f(x)=3x-2?
Is x+2/3 correct?

Thanks

reinsuranc
Jan 25, 2006, 08:39 PM
A.
f(u)=u^2+u and g(x)=2x+1
Let u=g(x)=2x+1
f(g(x))=f(u)=(2x+1)^2+(2x+1).


B.
I don't understand the next part of the problem.
You have not defined g(circle)f.


C.
y=f(x)=3x-2
x=(y+2)/3=f^(-1)

Damian616
Mar 31, 2010, 11:19 AM
Let f(x)=5x^2-4x and g(x)=5x+1

Damian616
Mar 31, 2010, 11:19 AM
Let f(x)=5x^2-4x and g(x)=5x+1

Unknown008
Mar 31, 2010, 10:53 PM
Damian616, please, start your own thread.

InfoJunkie4Life
Apr 1, 2010, 01:51 PM
The circle thing can be read as "of"

It is just a different form of notation...

it will be the same as g of f of x.