Question

Which of the following options is a Pythagorean Identity

Answer 1

C is the answer to this question

Answer 2

None of them really, but C is equivalent to the Triognometric Pythagorean Theorem:

$(\sin x + \cos x)^2 = 1 + 2 \sin x \cos x$

$\sin^2 x + 2 \sin x \cos x + \cos ^2 x = 1 + 2 \sin x \cos x$

$\sin^2x + \cos ^2x = 1$

That's the Trigonometric Pythagorean Theorem

Answer: C