document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=127841>Question 127841</A>: <I><SPAN STYLE=\"word-break: break-all;\"> use g(x)=5/(1-2x) and f(x)=1-x^2\r<BR>\n" );
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document.write( "find f(-5)\r<BR>\n" );
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document.write( "find the domain of g(x) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #93635 by </B><A HREF=/tutors/aboutme.mpl?userid=solver91311><B>solver91311(24713)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=solver91311><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=solver91311><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=93635\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A word about function notation.  f or g or h is a function.  f(x) is the value of the function f at x, g(a) is the value of the function g at a.  \r<BR>\n" );
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document.write( "If <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=f%28x%29=1-x%5E2 ALIGN=MIDDLE  ALT=\"f%28x%29=1-x%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >, then <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1-x%5E2 ALIGN=MIDDLE  ALT=\"1-x%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > is the value of the function f at x, so f(-5) is the value of the function at -5, i.e. <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=f%28-5%29=1-%28-5%29%5E2 ALIGN=MIDDLE  ALT=\"f%28-5%29=1-%28-5%29%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  You do the arithmetic.\r<BR>\n" );
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document.write( "The domain of a function is the set of values for which the function is defined.  The given function g is a rational expression that is defined everywhere except where the denominator is zero.  So, if <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1-2x=0 ALIGN=MIDDLE  ALT=\"1-2x=0\"   DISABLED_style= \"max-width:90%; height:auto;\" >, then g is not defined.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1-2x=0 ALIGN=MIDDLE  ALT=\"1-2x=0\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-2x=-1 ALIGN=MIDDLE  ALT=\"-2x=-1\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=1%2F2 ALIGN=MIDDLE  ALT=\"x=1%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "So the domain of g is all real numbers except <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F2 ALIGN=MIDDLE  ALT=\"1%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  In interval notation:\r<BR>\n" );
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document.write( "(<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-infinity ALIGN=MIDDLE  ALT=\"-infinity\"   DISABLED_style= \"max-width:90%; height:auto;\" >,<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F2 ALIGN=MIDDLE  ALT=\"1%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >) U (<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F2 ALIGN=MIDDLE  ALT=\"1%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >,<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=infinity ALIGN=MIDDLE  ALT=\"infinity\"   DISABLED_style= \"max-width:90%; height:auto;\" >)\r<BR>\n" );
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document.write( "In set notation {x|x is real, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%3C%3E1%2F2 ALIGN=MIDDLE  ALT=\"x%3C%3E1%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >}\r<BR>\n" );
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document.write( " </SPAN>\n" );
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