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Problem
Problem
Consider the equations
5
sin
2
x
+
3
sin
x
cos
x
−
3
cos
2
x
=
2
…
(
i
)
5\sin^2 x + 3\sin x \cos x - 3\cos^2 x = 2 \quad \dots(i)
5
sin
2
x
+
3
sin
x
cos
x
−
3
cos
2
x
=
2
…
(
i
)
sin
2
x
−
cos
2
x
=
2
−
sin
2
x
…
(
i
i
)
\sin^2 x - \cos 2x = 2 - \sin 2x \quad \dots(ii)
sin
2
x
−
cos
2
x
=
2
−
sin
2
x
…
(
ii
)
If
tan
α
,
tan
β
\tan \alpha, \tan \beta
tan
α
,
tan
β
satisfy (i) and
cos
γ
,
cos
δ
\cos \gamma, \cos \delta
cos
γ
,
cos
δ
satisfy (ii), then
tan
α
⋅
tan
β
+
cos
γ
+
cos
δ
\tan \alpha \cdot \tan \beta + \cos \gamma + \cos \delta
tan
α
⋅
tan
β
+
cos
γ
+
cos
δ
can be equal to a. -1 b.
−
5
3
+
2
13
-\frac{5}{3} + \frac{2}{\sqrt{13}}
−
3
5
+
13
2
c.
5
3
−
2
13
\frac{5}{3} - \frac{2}{\sqrt{13}}
3
5
−
13
2
d.
5
3
+
2
13
\frac{5}{3} + \frac{2}{\sqrt{13}}
3
5
+
13
2
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