If secθ + tanθ = 2, then the value of sec θ

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sec θ + tan θ = 2 ......(i)
∴ sec² θ – tan² θ = 1
⇒ (sec θ + tan θ) (sec θ – tan θ) = 1

⇒ sec θ – tan θ =	1	......(ii)
	2

By adding equations (i) and (ii),
∴ sec θ + tan θ + sec θ – tan θ

= 2 +		1	=	5
		2		2

⇒ 2 sec θ =		5	⇒ sec θ =	5
		2		4