document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=39854>Question 39854</A>: <I><SPAN STYLE=\"word-break: break-all;\"> what is the domain of function y=squaroot of x2-9<BR>\n" );
document.write( "show answer in two different ways<BR>\n" );
document.write( "a. algebraic solution<BR>\n" );
document.write( "b. graphical solution </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #25294 by </B><A HREF=/tutors/aboutme.mpl?userid=fractalier><B>fractalier(6550)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=fractalier><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=fractalier><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=25294\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Domain means \"all allowable values of x.\"<BR>\n" );
document.write( "For y = sqrt(x^2 - 9), <BR>\n" );
document.write( "notice that what's under the square root sign can never be negative, so we have to choose our x's such that x^2 - 9 is greater than or equal to zero...so that's what we write...<BR>\n" );
document.write( "x^2 - 9 &#8805; 0<BR>\n" );
document.write( "x^2 &#8805; 9<BR>\n" );
document.write( "|x| &#8805; 3<BR>\n" );
document.write( "or another way to write this is<BR>\n" );
document.write( "x &#8805; 3 or x &#8804; -3<BR>\n" );
document.write( "Graphically, there would be no graph between -3 and 3, since x doesn't exist there, so to speak...those numbers are not in the domain of the function... </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );