document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1183665>Question 1183665</A>: <I><SPAN STYLE=\"word-break: break-all;\">  1) The height of a nail in a bicycle tire as it rotates around is periodic in<BR>\n" );
document.write( "nature. The radius of the tire is 30cm and at the current pedaling speed the tire<BR>\n" );
document.write( "rotates once every second.<BR>\n" );
document.write( "a. Determine the equation of a sinusoidal function that models this situation<BR>\n" );
document.write( "assuming that the nail starts on the ground at time zero.<BR>\n" );
document.write( "b. At what time(s) during the first two seconds is the nail at a height of 30cm?\r<BR>\n" );
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document.write( " 2) A swimmer on a floating air mattress will follow the rise and fall of the waves in the lake. When the person is on the top of the wave her feet are 1.5m above the average surface height of the lake. When she is in a trough her feet dig 0.5m into the water (-0.5m). The peaks of the waves are separated by two seconds. Create an equation of the sinusoidal function that models this movement assuming that she starts at the average surface height of the lake and heads upwards. \r<BR>\n" );
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document.write( " 3) Prove the following trig identities: \r<BR>\n" );
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document.write( "a) tan 2x- 2tan 2x sin^2x= sin 2 x\r<BR>\n" );
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document.write( "b) sec^2x-2sec x cos x + cos^2x= tan^2x- sin^2 x  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #814077 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52943)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=814077\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .\r<BR>\n" );
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