document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=960729>Question 960729</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Let t be a real number with cos(t)=3/7, 3pi/2<t<2pi \r<BR>\n" );
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document.write( "Find the exact value for each of the following: \r<BR>\n" );
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document.write( "a. sin(t+3pi/2) <BR>\n" );
document.write( "b. sec(-t) <BR>\n" );
document.write( "c. cos(2pi) <BR>\n" );
document.write( "d.cos(4pi/3 - t) \r<BR>\n" );
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document.write( "Please explain what these means how these are solved I have to understand! \r<BR>\n" );
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document.write( "Thank you! in advance </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #587175 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=587175\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let t be a real number with cos(t)=3/7, 3pi/2 Find the exact value for each of the following:<BR>\n" );
document.write( "Note:: If cos(t) = 3/7, sin(t) = sqrt[7^2-3^2]/7 = 2sqrt(10)/7<BR>\n" );
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document.write( "a. sin(t+3pi/2) -sin(t) = -3/7<BR>\n" );
document.write( "Use the formula for sin(a+b) = sin(a)cos(b)+cos(a)sin(b)<BR>\n" );
document.write( "= (2sqrt(10)/7)(0)+(3/7)(-1) = -3/7<BR>\n" );
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document.write( "b. sec(-t) = 1/cos(-t) = 1/cos(t) = 7/3<BR>\n" );
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document.write( "c. cos(2pi) = cos(0) = 1<BR>\n" );
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document.write( "d.cos(4pi/3 - t) = cos(4pi/3)*cos(t)+sin(4pi/3)*sin(t)<BR>\n" );
document.write( "= (-cos(pi/3)*(3/7)+(-sin(pi/3)(2sqrt(10)/7)<BR>\n" );
document.write( "= (-1/2)(3/7)+(-sqrt(3)/2)(2sqrt(10)/7)<BR>\n" );
document.write( "= (-3/14)-2sqrt(30)/14<BR>\n" );
document.write( "= -(3+2sqrt(30))/14<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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document.write( "Please explain what these means how these are solved I have to understand! <BR>\n" );
document.write( " </SPAN>\n" );
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