document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=401144>Question 401144</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Angle A is acute and such that tanA=&#8730;6/3.\r<BR>\n" );
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document.write( "(a) Show clearly that the exact value of sin A can be written in the form 1/5&#8730;k and state the value of k.\r<BR>\n" );
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document.write( "(b) Hence, or otherwise, show that the value of cos2A is exactly 1/5 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #284011 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=284011\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> (a)<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=tan+A+=+sqrt%286%29%2F3+=+%28sqrt%286%29%2Fsqrt%2815%29%29%2F%283%2Fsqrt%2815%29%29+=+sin+A%2FcosA ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "==> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin+A+=+sqrt%286%29%2Fsqrt%2815%29+=+sqrt%282%29%2Fsqrt%285%29+=+sqrt%2810%29%2F5+=+%281%2F5%29%2Asqrt%2810%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "(b)<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cos+%282A%29+=+1-2sin%5E2%28A%29+=+1+-+2%2A%2810%2F25%29+=+1+-+4%2F5+=+1%2F5 ALIGN=MIDDLE  ALT=\"cos+%282A%29+=+1-2sin%5E2%28A%29+=+1+-+2%2A%2810%2F25%29+=+1+-+4%2F5+=+1%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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