document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1029938>Question 1029938</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hi, I'm having trouble understanding and solving this problem:\r<BR>\n" );
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document.write( "f(x)= x^2 + 9 is shown.<BR>\n" );
document.write( "Which interval of x restricts the domain of f(x) such that f^-1(x) exists?<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 #644848 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=644848\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> f(x)= x^2 + 9 is shown.<BR>\n" );
document.write( "Which interval of x restricts the domain of f(x) such that f^-1(x) exists?<BR>\n" );
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document.write( "y = x^2 + 9 is a parabola symmetric to the y-axis.<BR>\n" );
document.write( "It's inverse would be a parabola symmetric to the x-axis<BR>\n" );
document.write( "and that is not a function.<BR>\n" );
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document.write( "But it's inverse would be a function if you restrict<BR>\n" );
document.write( "x to [0,+oo) for f(x).<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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