Question #2077e

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Question #2077e

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Answer 1 · 2017-11-24T13:10:56

This can't be proved, it is not an identity.

Explanation:

An identity states that this is true for all $x$ $x$ .

Let $x = \frac{π}{2}$ $x=pi/2$

$2 {sin}^{2} (\frac{π}{2}) + 14 sin (\frac{π}{2}) cos (\frac{π}{2}) + 50 {cos}^{2} (\frac{π}{2}) = 26$ $2sin^2(pi/2)+14sin(pi/2)cos(pi/2)+50cos^2(pi/2)=26$

$2 (1) + 14 (1) (0) + 50 (0) = 26$ $2(1)+14(1)(0)+50(0)=26$

$2 \neq 26$ $2!=26$

FALSE

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Question #2077e

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