document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1034868>Question 1034868</A>: <I><SPAN STYLE=\"word-break: break-all;\"> explain why x=4 is not in the domain of the function f(x)= square root x-5? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #649526 by </B><A HREF=/tutors/aboutme.mpl?userid=harpazo><B>harpazo(655)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=harpazo><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=harpazo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=649526\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If you replace x with 4 in the given function the answer becomes root(-1).\r<BR>\n" );
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document.write( "The root of negative numbers does not exist in the real number system.\r<BR>\n" );
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document.write( "This is why x cannot be 4. The value of x = 4 stands outside the domain of the \r<BR>\n" );
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document.write( "function. \r<BR>\n" );
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document.write( "Prove:\r<BR>\n" );
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document.write( "f(x) = root(x - 5)\r<BR>\n" );
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document.write( "f(4) = root(4 - 5)\r<BR>\n" );
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document.write( "f(4) = root(-1)\r<BR>\n" );
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document.write( "So, x = 4 is undefined for this function.  </SPAN>\n" );
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