Question 962815
solve the equation, [0, 2pi)
a) cos(pi/2+x)-cos(pi/2-x)=&#8730;2
(cos(&#960;/2)*cosx-sin(&#960;/2)*sinx-[(cos(&#960;/2)*cosx+sin(&#960;/2)*sinx]=&#8730;2
0*cosx-1*sinx-0*cosx-1*sinx=&#8730;2
-2sinx=&#8730;2
sinx=-&#8730;2/2
x=3&#960;/4, 5&#960;/4