If α + β = 90° and α : β = 2 : 1,

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If α + β = 90° and α : β = 2 : 1, then the ratio of cosα to cosβ is :

1. 1 : √3
2. 1 : 3
3. 1 : √2
4. 1 : 2

Correct Option: A

α : β = 2 : 1
Sum of the terms of ratio
= 2 + 1 = 3
α + β = 90°

∴ α =	2	× 90° = 60°
	3

β = 30°

∴	cosα	=	cos 60°	=	1/2
	cosβ		cos 60°		√3/2

= 1 : √3