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Mathematics
Mathematics
Problem
For an acute angle
θ
\theta
θ
,
sin
θ
=
2
x
x
2
+
4
\sin\theta = \dfrac{2x}{\sqrt{x^{2}+4}}
sin
θ
=
x
2
+
4
2
x
where
x
>
0
x>0
x
>
0
. Express
cos
θ
\cos\theta
cos
θ
in its simplest form in terms of
x
x
x
.
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