\r\n" );
document.write( "You were told not to use any calculators. The other tutor evaluated angles, \r\n" );
document.write( "which requires a calculator so you cannot use the part where he evaluated angles\r\n" );
document.write( "to find which quadrant 
is in.
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document.write( "(a) find the value of 
...\r\n" );
document.write( "\r\n" );
document.write( "Please refer to the graph below.\r\n" );
document.write( "\r\n" );
document.write( "Since 
is negative and in QIV, it is measured clockwise from the right side of the\r\n" );
document.write( "x-axis. Since 
we take xα=+3. We know it's POSITIVE because it goes to \r\n" );
document.write( "the right. We always take rα as positive. \r\n" );
document.write( "r=
. Then, we find yα by \r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "and we know to use the NEGATIVE sign because yα goes DOWN from the x-axis.\r\n" );
document.write( "\r\n" );
document.write( "Since 
is positive, it is in QIII, measured counter-clockwise from the right\r\n" );
document.write( "side of the x-axis. Since 
we take yβ=-5, rβ=13. Then,\r\n" );
document.write( "we find xβ by \r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "and again, we know to use the NEGATIVE sign because xβ goes LEFT of the y-axis.\r\n" );
document.write( "So xβ = -12. So we can plot both angles and their triangles on the same graph,\r\n" );
document.write( "without one overlapping the other:\r\n" );
document.write( "\r\n" );
document.write( "
\n" );
document.write( "(a) find the value of ... 
\r\n" );
document.write( "First find 
\r\n" );
document.write( "\r\n" );
document.write( "Next find 
\r\n" );
document.write( "\r\n" );
document.write( "Next find 
\r\n" );
document.write( "
\r\n" );
document.write( "\r\n" );
document.write( "Finally, 
\r
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document.write( "\n" );
document.write( "(a) find the values of... 
\r\n" );
document.write( "We already have cos(2a+b), and we know that 
.\r\n" );
document.write( "\r\n" );
document.write( "We find 
\r\n" );
document.write( "\r\n" );
document.write( "
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document.write( "(b) determine the quadrant which contains . Give reasons\r\n" );
document.write( "Now if you've learned \"ALL STUDENTS TAKE CALCULUS\" or some other way to\r\n" );
document.write( "determine which trig ratios are positive or negative in which quadrants,\r\n" );
document.write( "you know that the cosine is negative only in QII and QIII, and the tangent \r\n" );
document.write( "is negative only in QII and QIV.\r\n" );
document.write( "\r\n" );
document.write( "Since is negative and is also negative, then is in QII.\r\n" );
document.write( " \r\n" );
document.write( "Edwin
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document.write( "![\"\"](\"/images/stars/stars-13.gif\")
