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Cosb= A. cosb B. sina C. cosa OD. sinb [sin (a + b) + sin(a - b)] OOO MONETHE

Cosb= A. cosb B. sina C. cosa OD. sinb [sin (a + b) + sin(a - b)] OOO MONETHE-example-1
User Inoabrian
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1 Answer

24 votes
24 votes

Answer: B. sin a

Step-by-step explanation

• Expression,


_(---)\cos b=(1)/(2)\left[\sin\left(a+b\right)+\sin\left(a-b\right)\right]

If we use the properties we get that:


2\sin a\cos b=\left[\sin\left(a+b\right)+\sin\left(a-b\right)\right]

Then:


\sin a\cos b=(1)/(2)\left[\sin\left(a+b\right)+\sin\left(a-b\right)\right]

User Karol S
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