Multiple choice general knowledge sin^2x+ cos^2x= 0 1 90 -1 Reveal answer Fill a bubble to check yourself B Correct answer Explanation The Pythagorean identity states that sin²x + cos²x = 1 for any angle x. This is one of the fundamental identities in trigonometry derived from the unit circle definition. Options 0, 90, and -1 are incorrect values for this expression.