document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=24976>Question 24976</A>: <I><SPAN STYLE=\"word-break: break-all;\"> i have a question that appears on your site, however as i progressed with my answer i have come to a difficult point and am stuck. this is what i have got so far;\r<BR>\n" );
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document.write( "E=Fs<BR>\n" );
document.write( " =7sin(t-60)*4sin(t+30) which can use the idenitity-\r<BR>\n" );
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document.write( "2sinAsinB=cos(A+B)-cos(A+B)<BR>\n" );
document.write( "         =0.5(cos((t-60)-(t+30))-cos((t-60)+(t+30)))<BR>\n" );
document.write( "         =0.5(cos(t-60-t-30)-cos(t-60+t+30))<BR>\n" );
document.write( "         =0.5(cos(-90)-cos(2t-30))<BR>\n" );
document.write( "         =0.5*0-cos(2t-30)\r<BR>\n" );
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document.write( "And thats where i got up to, i know the answer should some how get to;\r<BR>\n" );
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document.write( "       -14cos(2t-30)\r<BR>\n" );
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document.write( "But i just cannot get there, can you tell me where i am going wrong and point me there please.\r<BR>\n" );
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document.write( "this is the question; the displacement of a body is given by s=4sin(t+30), and a force acting upon the body is given by F=7sin(t-60). If the energy of the motion, E, at time t is the product Fs, show that E=-14cos(2t-30) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #13358 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=13358\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Somewhere along the line you forgot the \"7\" and the \"4\"<BR>\n" );
document.write( "that are part of your problem.  Multiply your answer by <BR>\n" );
document.write( "7*4 and you will have the answer you are looking for.\r<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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