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If alpha is a root of 25 cos^2 theta+5 c...

If `alpha` is a root of 25 `cos^2 theta+5 cos theta-12=0, pi/2 lt alpha lt pi`, then `sin 2alpha=`

A

`24/25`

B

`- 24/25`

C

`13/18`

D

`- 13/18`

Text Solution

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The correct Answer is:
B
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PATHFINDER-BASIC MATHEMATICS-QUESTION BANK
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