The value of cos 65° sin 25° + sin 65° cos 25° is

1. 0

2. 1

3. 2

4. 4

Since, angles are acute in the equation,

∴ cos(90° - θ) = sin θ and sin(90° - θ) = cos θ

Using above values in cos 65° sin 25° + sin 65° cos 25° we get,

⇒ cos 65° sin (90 - 65)° + sin 65° cos (90 - 65)°
⇒ cos 65° cos 65° + sin 65° sin 65°
⇒ cos² 65° + sin² 65°
⇒ 1.

Hence, Option 2 is the correct option.