Question: how to find the value of sin(15)? Solution : We shall write 150=450-300 And apply Sin(A-B) formula Sin(A-B) =Sin(A)Cos(B)-Cos(A)Sin(A) Therefore Sin(150) = Sin(450-300) =Sin(450)Cos(300)-Cos(450)Sin(300) Now we shall substitute following values into above formulas Sin(450) =1/√2 , Cos(300) = √3/2…
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