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Mathematics
Mathematics
Problem
If the normal at the point
P
(
θ
)
P(\theta)
P
(
θ
)
to the ellipse
x
2
14
+
y
2
5
=
1
\frac{x^2}{14} + \frac{y^2}{5} = 1
14
x
2
+
5
y
2
=
1
, intersect it again at the point
Q
(
2
θ
)
Q(2\theta)
Q
(
2
θ
)
, then
cos
θ
\cos \theta
cos
θ
is equal to a.
2
3
\frac{2}{3}
3
2
b.
−
2
3
-\frac{2}{3}
−
3
2
c.
3
2
\frac{3}{2}
2
3
d.
−
3
2
-\frac{3}{2}
−
2
3
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