document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=980200>Question 980200</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Good day\r<BR>\n" );
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document.write( "Determine the gradient of the tangents at the given points. \r<BR>\n" );
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document.write( "f(x) = x² - x - 6 ....where y = -4\r<BR>\n" );
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document.write( "The answer is +-3 <BR>\n" );
document.write( "I just don't know how to get there </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #601390 by </B><A HREF=/tutors/aboutme.mpl?userid=Cromlix><B>Cromlix(4381)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Cromlix><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=Cromlix><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=601390\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> hi there,<BR>\n" );
document.write( "First set up your equation:<BR>\n" );
document.write( "f(x) = x^2 - x - 6 <BR>\n" );
document.write( "where y = -4<BR>\n" );
document.write( "Therefore,<BR>\n" );
document.write( "x^2 - x - 6 = -4<BR>\n" );
document.write( "Collect like terms<BR>\n" );
document.write( "x^2 - x - 6 + 4 = 0<BR>\n" );
document.write( "x^2 - x - 2 = 0<BR>\n" );
document.write( "Factorise<BR>\n" );
document.write( "(x + 1)(x - 2)= 0<BR>\n" );
document.write( "x + 1 = 0<BR>\n" );
document.write( "x = -1<BR>\n" );
document.write( "x - 2 = 0<BR>\n" );
document.write( "x = +2<BR>\n" );
document.write( "Differentiate:<BR>\n" );
document.write( "y = x^2 - x - 6<BR>\n" );
document.write( "dy/dx = 2x - 1<BR>\n" );
document.write( "Substitute the two 'x' values<BR>\n" );
document.write( "into the differentiated equation:<BR>\n" );
document.write( "......<BR>\n" );
document.write( "2x - 1<BR>\n" );
document.write( "(x = - 1)<BR>\n" );
document.write( "= 2(-1) - 1<BR>\n" );
document.write( "= -2 - 1<BR>\n" );
document.write( "= - 3<BR>\n" );
document.write( ".......<BR>\n" );
document.write( "2x - 1<BR>\n" );
document.write( "(x = 2)<BR>\n" );
document.write( "= 2(2) - 1<BR>\n" );
document.write( "= 4 - 1<BR>\n" );
document.write( "= 3<BR>\n" );
document.write( "......<BR>\n" );
document.write( "Therefore gradients are +-3<BR>\n" );
document.write( "Hope this helps:-) </SPAN>\n" );
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