document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1147270>Question 1147270</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Determine which of the following functions have inverse. Assume their domains are the set of real numbers unless specified otherwise. Derive the inverse function, x = f−1(y), where applicable.<BR>\n" );
document.write( "(a) y=21+7x (b) y = x2 + 5<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #803769 by </B><A HREF=/tutors/aboutme.mpl?userid=CubeyThePenguin><B>CubeyThePenguin(3113)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=CubeyThePenguin><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/cgi-bin/show-face.mpl?user=CubeyThePenguin><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=803769\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a) y = 7x + 21<BR>\n" );
document.write( "y - 21 = 7x<BR>\n" );
document.write( "(y - 21)/7 = x\r<BR>\n" );
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document.write( "f^(-1)(y) = (y - 21)/7\r<BR>\n" );
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document.write( "b) y = x^2 + 5<BR>\n" );
document.write( "y - 5 = x^2<BR>\n" );
document.write( "sqrt(y - 5) = x\r<BR>\n" );
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document.write( "f^(-1)(y) = sqrt(y - 5)\r<BR>\n" );
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