document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=131065>Question 131065</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hello,\r<BR>\n" );
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document.write( "I am having a hard time understanding the concept of even and odd Trigonometric Functions and have come to a problem I just do not understand how to solve.  The problem is:\r<BR>\n" );
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document.write( "Use the even-odd properties to find the exact value of the expression. It may be helpful to draw the unit circle graph. I can input this into a calculator to get the answer, but I need to learn and understand for future studies.  \r<BR>\n" );
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document.write( "sin(-pi)\r<BR>\n" );
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document.write( "Any help or explanation in layman's terms would be appreciated. Thanks so much!  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #95693 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=95693\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> sin(-pi)<BR>\n" );
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document.write( "Draw the unit circle on a coordinate system.<BR>\n" );
document.write( "Four points on the circle:<BR>\n" );
document.write( "At 0 radians you have (1,0)<BR>\n" );
document.write( "At pi/2 you have (0,1)<BR>\n" );
document.write( "At pi you have (-1,0)<BR>\n" );
document.write( "At (3/2)pi you have (0,-1)<BR>\n" );
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document.write( "The point (-1,0) is at pi radians and at -pi radians.<BR>\n" );
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document.write( "The y-value for each of these points (and all other points <BR>\n" );
document.write( "on the circle, is the sine of the corresponding angle.<BR>\n" );
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document.write( "So, sin(-pi) = 0<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.\r<BR>\n" );
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