Math
posted by Prince .
Without using calculator,evaluate Sin15 deg,Cos 15 deg,Sin 75deg. O need the answer urgently pls.

Math 
Reiny
sin 15°
= sin(4530)
= sin45cos30  cos45sin30
= (1/√2)(√3/2)  (1/√2)(1/2)
= (√3  1)/(2√2)
so cos 15° the same way
and for the last : sin(75°) = sin(45+30)
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