document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=187708>Question 187708</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/032129646X/algebrahomeworkh>Precalculus</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Hi,<BR>\n" );
document.write( "I'm trying to find the inverse function of: f(x) = 8x^3 - 1<BR>\n" );
document.write( "Not really sure how to approach this one. I've plotted points on a graph and took the inverses of those points, but I can't come up with a function to get those points.<BR>\n" );
document.write( "Thanks,<BR>\n" );
document.write( "Lynn </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #140734 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=140734\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> find the inverse function of: f(x) = 8x^3 - 1<BR>\n" );
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document.write( "When it comes to functions, inverse means \"interchange the x and the y values<BR>\n" );
document.write( "in all the points.  So, if f has point (1,2), f^-1 will have point (2,1).<BR>\n" );
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document.write( "You have y = 8x^3-1<BR>\n" );
document.write( "1st: Interchange x and y to get<BR>\n" );
document.write( "x = 8y^3-1<BR>\n" );
document.write( "2nd Solve for y<BR>\n" );
document.write( "8y^3 = x+1<BR>\n" );
document.write( "y^3 = (x+1)/8<BR>\n" );
document.write( "y = [cbrt(x+1)]/2<BR>\n" );
document.write( "That is the inverse of y = 8x^3-1<BR>\n" );
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document.write( "I'll graph both so you can see how interchanging x and y looks on a graph.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28400%2C300%2C-10%2C10%2C-10%2C10%2C8x%5E3-1%2C%281%2F2%29%28x%2B1%29%5E%281%2F3%29%29 ALIGN=MIDDLE  ALT=\"graph%28400%2C300%2C-10%2C10%2C-10%2C10%2C8x%5E3-1%2C%281%2F2%29%28x%2B1%29%5E%281%2F3%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );