θ is an acute angle and sin θ and cos θ are given. Use identities to find the indicated value.
-$\sin ^ { 2 } 20 ^ { \circ } + \cos ^ { 2 } 20 ^ { \circ }$
A) 1
B) 0
C) $0.20$
D) $0.04$

Question

Quizplus · Accepted Answer

This is a direct application of the Pythagorean identity for trigonometric functions, which states that $\sin^2\theta + \cos^2\theta = 1$ for any angle $\theta$.

θ Is an Acute Angle and Sin θ and Cos sin⁡220∘+cos⁡220∘\sin ^ { 2 } 20 ^ { \circ } + \cos ^ { 2 } 20 ^ { \circ }sin220∘+cos220∘

θ Is an Acute Angle and Sin θ and Cos $\sin ^ { 2 } 20 ^ { \circ } + \cos ^ { 2 } 20 ^ { \circ }$