If sin 5 θ = cos 20° ( 0° < θ < 90°) then

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If sin 5 θ = cos 20° ( 0° < θ < 90°) then the value of θ is

1. 4°
2. 22°
3. 10°
4. 14°

Correct Option: D

sin 5θ = cos20°
⇒ sin 5θ = sin (90 – 20) = sin 70°
⇒ 5θ = 70°

⇒ θ =	70	= 14°
	5