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Mathematics
Mathematics
Problem
If
sin
x
=
3
5
\sin x = \dfrac{3}{5}
sin
x
=
5
3
and
0
<
x
<
π
2
0 < x < \dfrac{\pi}{2}
0
<
x
<
2
π
, find
cos
2
x
\cos 2x
cos
2
x
. a)
16
25
\dfrac{16}{25}
25
16
b)
7
25
\dfrac{7}{25}
25
7
c)
−
7
25
-\dfrac{7}{25}
−
25
7
d)
1
5
\dfrac{1}{5}
5
1
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