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The value of : (1+cos frac (pi)(6)) (1+c...

The value of : `(1+cos frac (pi)(6)) (1+cos frac (pi)(3))(1+cos frac (2pi)(3)) (1+cos frac (7pi)(6))` is:

A

`3/16`

B

`3/8`

C

`3/4`

D

`1/2`.

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MODERN PUBLICATION-TRIGNOMETRY-EXERCISE
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  2. In triangle ABC, if sin Asin B=(ab)/c^2, then the triangle is :

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  9. If A+B=45^@ then then (cot A- 1) (cot B- 1) is equal to :

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