document.write( "Question 551020: If f(x)= $\"x%5E3%2B1\"$ and $\"f%5E-1\"$ is the inverse function of f, what is $\"f%5E-1\"$ (4)? \n" ); document.write( "

Algebra.Com's Answer #359465 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

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If f(x)= $\"x%5E3%2B1\"$ and $\"f%5E-1\"$ is the inverse function of f, what is $\"f%5E-1\"$ (4)?
\n" ); document.write( "y = f(x)
\n" ); document.write( "y = x^3 + 1
\n" ); document.write( "Find the inverse equation, replace x with y, solve for y
\n" ); document.write( "x = y^3 + 1
\n" ); document.write( "x - 1 = y^3
\n" ); document.write( "y = $\"3sqrt%28x-1%29\"$ ; that's the cube root of (x-1)
\n" ); document.write( "when x = 4
\n" ); document.write( "y = $\"3sqrt%284-1%29\"$ ;
\n" ); document.write( "y = $\"3sqrt%283%29\"$ ;
\n" ); document.write( "or
\n" ); document.write( "y = $\"3%5E%281%2F3%29\"$
\n" ); document.write( " $\"f%5E-1\"$ (4) = 1.44225 \n" ); document.write( "

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