document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1172059>Question 1172059</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Question:  If tan\theta =5/12, 0<=theta <=90, then cos theta = ?\r<BR>\n" );
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document.write( "My answer:  Tan =  Sin/Cos and therefore cos = 12.\r<BR>\n" );
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document.write( "I am wrong per the answer in the book. Can someone please explain to me why am I wrong. The answer in the book is 12/5 which seems to be the inverse of the tan!\r<BR>\n" );
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document.write( "Thank you </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #796968 by </B><A HREF=/tutors/aboutme.mpl?userid=math_helper><B>math_helper(2461)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=math_helper><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=math_helper><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=796968\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "You can sanity check your answer by remembering  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+-1+%3C=+cos%28x%29+%3C=+1+ ALIGN=MIDDLE  ALT=\"+-1+%3C=+cos%28x%29+%3C=+1+\"   DISABLED_style= \"max-width:90%; height:auto;\" >, so clearly neither 12 nor 12/5 can be correct.   This is true for sin(x) as well, but not true for tan(x).<BR>\n" );
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document.write( "It is often best to draw a triangle for these types of problems.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+drawing%28400%2C200%2C-1%2C15%2C-1%2C8%2C+grid%280%29%2C%0D%0A++++++++++++line%280%2C0%2C12%2C0%29%2C%0D%0A++++++++++++line%2812%2C0%2C12%2C5%29%2C%0D%0A++++++++++++line%280%2C0%2C12%2C5%29%2C%0D%0A+++++++++++locate%2812.2%2C2.5%2C%225%22%29%2C%0D%0A+++++++++++locate%286.5%2C3.5%2Cblue%28%2213%22%29%29%2C%0D%0A+++++++++++locate%286.2%2C0.8%2C%2212%22%29%2C%0D%0A+++++++++++locate%281.9%2C0.8%2C+theta%29%0D%0A%0D%0A%29+ ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+tan%28theta%29+=+5%2F12+ ALIGN=MIDDLE  ALT=\"+tan%28theta%29+=+5%2F12+\"   DISABLED_style= \"max-width:90%; height:auto;\" >  ..... opp/adj<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+hypotenuse+=+sqrt%2812%5E2+%2B+5%5E2%29+=+13+ ALIGN=MIDDLE  ALT=\"+hypotenuse+=+sqrt%2812%5E2+%2B+5%5E2%29+=+13+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+cos%28theta%29+=+12%2F13+ ALIGN=MIDDLE  ALT=\"+cos%28theta%29+=+12%2F13+\"   DISABLED_style= \"max-width:90%; height:auto;\" > ..... adj/hyp\r<BR>\n" );
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document.write( "Just thought to add this, as you might find it helpful.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+tan%28theta%29+=+sin%28theta%29%2Fcos%28theta%29+ ALIGN=MIDDLE  ALT=\"+tan%28theta%29+=+sin%28theta%29%2Fcos%28theta%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > \r<BR>\n" );
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document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+sin%28theta%29+=+5%2F13+ ALIGN=MIDDLE  ALT=\"+sin%28theta%29+=+5%2F13+\"   DISABLED_style= \"max-width:90%; height:auto;\" >  ..... opp/hyp\r<BR>\n" );
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document.write( "So, for this problem,  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+sin%28theta%29%2Fcos%28theta%29+ ALIGN=MIDDLE  ALT=\"+sin%28theta%29%2Fcos%28theta%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28%285%2F13%29%29%2F%28%2812%2F13%29%29+ ALIGN=MIDDLE  ALT=\"+%28%285%2F13%29%29%2F%28%2812%2F13%29%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+5%2F12+ ALIGN=MIDDLE  ALT=\"+5%2F12+\"   DISABLED_style= \"max-width:90%; height:auto;\" >  = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+tan%28theta%29+ ALIGN=MIDDLE  ALT=\"+tan%28theta%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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