document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=383273>Question 383273</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find cos (theta) and sin (theta) if the terminal side of (theta) lies along the line y = - 2 x in<BR>\n" );
document.write( "quadrant IV. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #271418 by </B><A HREF=/tutors/aboutme.mpl?userid=robertb><B>robertb(5830)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=robertb><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=robertb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=271418\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If the terminal side of <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=theta ALIGN=MIDDLE  ALT=\"theta\"   DISABLED_style= \"max-width:90%; height:auto;\" > lies along the line y = - 2 x in<BR>\n" );
document.write( "quadrant IV, then <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=tan%28theta%29+=+y%2Fx+=+-2 ALIGN=MIDDLE  ALT=\"tan%28theta%29+=+y%2Fx+=+-2\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  From the identity <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2B%28tan%28theta%29%29%5E2+=+%28sec%28theta%29%29%5E2 ALIGN=MIDDLE  ALT=\"1%2B%28tan%28theta%29%29%5E2+=+%28sec%28theta%29%29%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >, we get <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28sec%28theta%29%29%5E2+=+5 ALIGN=MIDDLE  ALT=\"%28sec%28theta%29%29%5E2+=+5\"   DISABLED_style= \"max-width:90%; height:auto;\" >, or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sec%28theta%29+=+sqrt%285%29 ALIGN=MIDDLE  ALT=\"sec%28theta%29+=+sqrt%285%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, since secant is positive in the 4th quadrant.  Then <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cos%28theta%29+=+1%2Fsqrt%285%29 ALIGN=MIDDLE  ALT=\"cos%28theta%29+=+1%2Fsqrt%285%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  From this we get <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%28theta%29+=+-2%2Fsqrt%285%29 ALIGN=MIDDLE  ALT=\"sin%28theta%29+=+-2%2Fsqrt%285%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
document.write( " </SPAN>\n" );
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