Let <span>sin(90° - )------------------------ > sin (90-x)
</span>sin(a - b<span>) = sin a*cos b - cos a*sin b </span><span>so </span>sin(90 - x) = sin 90*cos x - cos 90 * sin x sin(90 - x) = 1*cos x - 0* sin x-------- > cos x
the answer is the option <span>D. cos()</span><span>
