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    • Thread Starter
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    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...
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    It's an inverse function.

    let y= 5x+3

    solve for x by making it the subject

    swap x for y

    bang bang
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    (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.
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    the answer therefore is? im still dont get it sorry
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    (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.
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    (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
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    (Original post by Sammyboy1234)
    the answer therefore is? im still dont get it sorry
    Its not allowed to post answers on TSR. Sorry.
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    (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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