document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=698381>Question 698381</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Determine whether the given quadratic function has a minimum value or maximum value. Then find the coordinates of the minimum or maximum point.\r<BR>\n" );
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document.write( "f(x) = -x2 - 2x - 6 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #430616 by </B><A HREF=/tutors/aboutme.mpl?userid=Simnepi><B>Simnepi(216)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Simnepi><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=Simnepi><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=430616\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> to find whether a maximum or minimum differentiate the function twice<BR>\n" );
document.write( "f'(x) = -2x - 2<BR>\n" );
document.write( "f''(x) = -2<BR>\n" );
document.write( "since this is <0 the point is a local maximum<BR>\n" );
document.write( "at local atationary points f'(x) = 0<BR>\n" );
document.write( "so -2x - 2 = 0<BR>\n" );
document.write( "which gives  -2x = 2<BR>\n" );
document.write( "therefore x = -1 (your x coordinate)<BR>\n" );
document.write( "substitute this value into the original equation<BR>\n" );
document.write( "f(x) = -(-1)^2 - 2(-1) - 6<BR>\n" );
document.write( "f(x) = -5 (your y coordinate)<BR>\n" );
document.write( "therefore the coordinates are (-1,-5) and it's a maximum<BR>\n" );
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