document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1172993>Question 1172993</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If the equations y = sin x and y = cos x are both graphed on the same xy-axis system, the curves will intersect many times. Find coordinates for at least two intersection points.  </SPAN>\n" );
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document.write( "They intersect when sin(x) = cos(x)...<br><BR>\n" );
document.write( "which is when sin(x)/cos(x) = tan(x) = 1...<br><BR>\n" );
document.write( "which is when the angle x is 45 degrees in quadrant I or when it is 225 degrees in quadrant III.<br><BR>\n" );
document.write( "They also intersect when the angle is any multiple of 360 degrees more than either 45 degrees or 225 degrees.<br><BR>\n" );
document.write( "At 45 degrees, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%28x%29+=+cos%28x%29+=+sqrt%282%29%2F2 ALIGN=MIDDLE  ALT=\"sin%28x%29+=+cos%28x%29+=+sqrt%282%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "At 225 degrees, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%28x%29+=+cos%28x%29+=+-sqrt%282%29%2F2 ALIGN=MIDDLE  ALT=\"sin%28x%29+=+cos%28x%29+=+-sqrt%282%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "ANSWERS (angles in degrees):<BR>\n" );
document.write( "(45, sqrt(2)/2); (225, -sqrt(2)/2)<br><BR>\n" );
document.write( " </SPAN>\n" );
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