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1. if f(x)=5x+3
find f-1(x)
the -1 is a power but i cant write it properly here....
is (X) 1 im really not sure...
2. It's an inverse function.

let y= 5x+3

solve for x by making it the subject

swap x for y

bang bang
3. (Original post by amaraub)
It's an inverse function.

let y= 5x+3

solve for y

swap x for y

bang bang
I like the bang bang, don't forget to finalise the answer by letting f-1(x) equal your new equation.
4. the answer therefore is? im still dont get it sorry
5. (Original post by Sammyboy1234)
if f(x)=5x+3
find f-1(x)
the -1 is a power but i cant write it properly here....
is (X) 1 im really not sure...
Let fx=y make x the subject of the equation. Then put x in place of all the y u got after making x the subject.
6. (Original post by AmmarTa)
I like the bang bang, don't forget to finalise the answer by letting f-1(x) equal your new equation.
ahh yes

(Original post by Sammyboy1234)
the answer therefore is? im still dont get it sorry
i dont think im allowed to say

follow the steps i gave you
7. (Original post by Sammyboy1234)
the answer therefore is? im still dont get it sorry
Its not allowed to post answers on TSR. Sorry.
8. (Original post by Sammyboy1234)
the answer therefore is? im still dont get it sorry
i edited the steps, sorry i messed them up before

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