document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=889604>Question 889604</A>: <I><SPAN STYLE=\"word-break: break-all;\"> the values for x(3pi/2) and y(3pi/2) for x(t)=cos(t),y(t)=sin(t) are\r<BR>\n" );
document.write( "\n" );
document.write( "A)(0,-1)<BR>\n" );
document.write( "B)(.5, sqrt(3)/2)<BR>\n" );
document.write( "C)(-.5,0)<BR>\n" );
document.write( "D)(-.5,-sqrt(3)/2) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #538321 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=538321\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> i believe your solution is selection A which is (0,-1)\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "3pi/2 radians * 180 / pi = 3*180/2 degrees = 270 degrees.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "cos(3pi/2) = cos(270) = 0\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "sin(3pi/2) = sin(270) = -1\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "the reference angle for 270 is equal to 270 - 180 if you assume quadrant 3, or 360 - 270 if you assume quadrant 4.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "since 270 is on the border between quadrant 3 and quadrant 4, it can be assumed to be in either one, both of which get you the same answer.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "so the reference angle is 270 - 180 = 90, or the reference angle is 360 - 270 = 90.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "the reference angle is 90 degrees.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "the cosine of 90 degrees is 0<BR>\n" );
document.write( "the cosine of 90 degrees is 1\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "that would be in quadrant 1.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "in quadrant 3, the cosine is negative which doesn't matter since the cosine is 0.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "in quadrant 4, the cosine is positive which doesn't matter since the cosine is 0.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "in quadrant 3, the sine is negative.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "in quadrant 4, the sine is negative.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "either way, you have:\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "cos(270) = 0<BR>\n" );
document.write( "sin(270) = -1\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "that's selection A.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "you are dealing with functional notation.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "x(t) = cos(t)<BR>\n" );
document.write( "y(t) = sin(t)\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "x(3pi/2) becomes cos(3pi/2)<BR>\n" );
document.write( "y(2pi/2) becomes sin(3pi/2)\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "in both cases, you replace t with 3pi/2.\r<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );