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# Minimum Value

I recently solved a trigonometric question which asked for the minimum value of the $$(\sin\theta + \csc\theta)^{2}+(\cos\theta +\sec\theta)^{2}$$.I found there ar two answers, which one of them is correct?

A)8 B)9

Note by Puneet Pinku
11 months, 1 week ago

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Hint: Expand and simplify the expression by using $$\sin^2 A + \cos^2 A = 1$$. Then apply double angle formula $$\sin(2A) = 2\sin A \cos A$$.

- 11 months, 1 week ago

I believe that you didn't check the conditions under which we could apply arithmetic mean - geometric mean.

Staff - 11 months, 1 week ago