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If cos A =3/4, then 32 sin ""A/2 cos ""...

If `cos A =3/4,` then ` 32 sin ""A/2 cos ""(5A)/(2)=`...........A) `sqrt7` B) `-sqrt7` C) `7` D) `-7`

A

`sqrt7`

B

`-sqrt7`

C

7

D

`-7`

Text Solution

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The correct Answer is:
B
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