If 4sin²θ – 1 = 0 and angle θ is less

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If 4sin²θ – 1 = 0 and angle θ is less than 90°, the value of cos²θ + tan²θ is : (Take 0° < θ < 90°)

4 sin²θ – 1 = 0
⇒ 4 sin²θ = 1

⇒ sin²θ =	1
	4

⇒ sinθ =	1	(∵ θ < 90°)
	2

∴sinθ = sin30°
⇒ θ = 30°
∴ cos²θ + tan²θ = cos²30° + tan²30°

=		9 + 4	=	13
		12		12