document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=653019>Question 653019</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Can someone please help me with this question? Find the domain of the function. \r<BR>\n" );
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document.write( "f(x)=     3<BR>\n" );
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document.write( "square root x-7   \r<BR>\n" );
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document.write( "type answer in interval notation. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #408202 by </B><A HREF=/tutors/aboutme.mpl?userid=Shana-D77><B>Shana-D77(132)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Shana-D77><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=Shana-D77><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=408202\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> When you're looking for domain, the only thing you ned to look for is where the function will be zero in the denominator.  We can't divide by zero, so zeros can't be in the denominator.  In your function you have a square root in the denominator, so you also have to look for where you would have a negative number under the square root sign because that wouldn't yield a real number, either. \r<BR>\n" );
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document.write( "So, what number would make the denominator zero?  Well, 7 would.  The square root of (7 - 7) = 0.  We can't have 0 in the denominator, so it's no good.  Any number less than 7 wouldn't work either because then you'd have the square root of a negative number in the denominator.  So, the numbers that will work down there are any number greater than 7.\r<BR>\n" );
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document.write( "Should this include 7?  No!  It can't because then we'd have that bad zero.  So in interval notation, this would be...\r<BR>\n" );
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document.write( "(7, infinity)\r<BR>\n" );
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document.write( "Soft brackets (instead of [ ]) because it can't include 7. </SPAN>\n" );
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