Question

if sin3theeta = cos (theeta-2), where 3theeta and (theeta-2) are both acute angles, the find the value of theeta

Answer 1

Answer:

Given, \sin 3\theta=\cos (\theta -2^0)sin3θ=cos(θ−2

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\Rightarrow \sin 3\theta = \cos (90 - 3\theta) = 1\times 1 = 1⇒sin3θ=cos(90−3θ)=1×1=1

\Rightarrow \cos (90 - 3\theta) = \cos (\theta - 2^{\circ})⇒ cos(90−3θ)=cos(θ−2

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\Rightarrow 90 - 3\theta = \theta - 2^{\circ}⇒90−3θ=θ−2

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\Rightarrow 4\theta = 88⇒4θ=88

\Rightarrow \theta = 22^{\circ}⇒θ=22

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