Question

Cos 50 degrees * sin 40 degrees + sin 50 degrees * cos 40 degrees

Answer 1

hope you can understand

Answer 2

1

Explanation:

Identities to be remembered :

sin θ = cos (90 - θ) or cos θ = sin (90 - θ)

sin² θ + cos² θ = 1

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Solving :

⇒ cos 50° × sin 40° + sin 50° cos 40°

⇒ cos 50° cos (90 - 40)° + sin 50° sin (90 - 40)°

⇒ cos² 50° + sin² 50°

⇒ 1