Question 904033
You can first convert each
angle to a positive angle
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A negative angle starts at {{{ 0*pi }}}
and rotates CW
The whole circle is {{{ 2*pi = ( 36/18)*pi }}}
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(a)
{{{ ( 36/18 )*pi - ( 25/18 )*pi = ( 11/18 )*pi }}}
That would be the positive version of the angle
which is arrived at by rotating CCW from {{{ 0*pi }}}
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Which quadrant is it in?
{{{ (9/18 )*pi }}} is 90 degrees
So, {{{ (11/18)*pi }}} is {{{ (2/18)*pi }}}
past 90 degrees ( 2nd quadrant )
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That means it makes an angle of
{{{ (7/18)*pi }}} with the horizontal
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The components of this angle are:
{{{ -cos( (7/18)*pi ) }}} ( x-coordinate )
{{{ sin( (7/18) *pi ) }}} ( y-coorinate )
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Hope this helps