Establish the identity.
19(sin²θ) + 20(cos²θ) = 19 + cos²θ
Which of the following shows the key steps in establishing the identity?
A. 19(sin²θ) + 20(cos²θ) = 19(sin²θ+cos²θ) + cos²θ = 19+cos²θ
B. 19(sin²θ) + 20(cos²θ) = 19 + 20(sin²θ + cos²θ) +sin²θ = 19 + cos²
C. 19(sin²θ) +20(cos²θ) = 19(sin²θ+cos²θ) + sin²θ = 19 + cos²θ
D. 19(sin²θ) +20(cos²θ) = 19 + 20(sin²θ + cos²θ) + cos²θ = 19 + cos²



Answer :

Answer:

option A

Step-by-step explanation:

sin^2+cos^2=1

as you know....