If A = sin² θ + cos4θ, for any value of

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When θ = 0°
sin²θ + cos⁴θ = 1
When θ = 45°,

sin²θ + cos⁴θ =		1	+	1	=	3
		2		4		4

when θ = 30°,

sin²θ + cos⁴θ =		1	+	9
		4		16

=		4 + 9	=	13
		16		16

Hence, the value of

A = sin²θ + cos⁴θ =	13
	16

	1	≤ A ≤ 1
	5

	13	≤ A ≤ 1
	16

		3	≤ A ≤	13
		4		16