document.write( "Question 15349: In reference to Inverse Functions: How do you determine when to use the \"short cut\" method when trying to find the inverse of a function? For example, f(x) y = (x3+8)/3 so, we cubed it, added 8, and then divided by 3. If you undo it in reverse order (multiply 3, minus 8, cube root) it becomes the inverse. \"f%5E%28-1%29%28x%29+=+root%283%2C3x-8%29\" Why won't this work on all the problems? Thank you in advance! \n" ); document.write( "
Algebra.Com's Answer #7618 by khwang(438)\"\" \"About 
You can put this solution on YOUR website!
You are right for the inverse of
\n" ); document.write( " f(x)= y = \"%28x%5E3%2B8%29%2F3\"
\n" ); document.write( " to get
\n" ); document.write( " y = \"+f%5E%28-1%29%28x%29+=+%283x-8%29%5E%281%2F3%29+\"
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\n" ); document.write( " But use ^ for exponent and parentehsis for grouping terms next time. \r
\n" ); document.write( "\n" ); document.write( " If the original function is constructed by elementary invertible
\n" ); document.write( " function (such as addition, multiplication,...) , we only need to
\n" ); document.write( " apply reverse process step by step to get the inverse function.
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\n" ); document.write( " Since y=f(x)= \"T%5Bk%5D\"\"T%5Bk-1%5D\"..\"T%5B1%5D%28x%29\" then
\n" ); document.write( " \"f%5E%28-1%29%28x%29\" = \"T%5B1%5D%5E%28-1%29\" \"T%5B2%5D%5E%28-1%29\"..\"T%5Bk%5D%5E%28-1%29%28x%29\"
\n" ); document.write( " (if each \"T%5Bi%5D+\" is invertible.]\r
\n" ); document.write( "\n" ); document.write( " By for some functions such as y = x/(x^2+1) (or the functions containing
\n" ); document.write( " some transcendental functions as trig or log )
\n" ); document.write( " is not so easy to get 1st inverse. I suggest that you try.
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\n" ); document.write( " Anyway, you have got good idea and good luck!!!\r
\n" ); document.write( "\n" ); document.write( " Kenny\r
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