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Mathematics
Mathematics
Problem
In right triangle PQR,
∠
Q
=
90
∘
\angle Q = 90^\circ
∠
Q
=
9
0
∘
and the hypotenuse
P
R
=
15
cm
PR = 15\,\text{cm}
P
R
=
15
cm
. If
P
Q
=
9
cm
PQ = 9\,\text{cm}
P
Q
=
9
cm
, let
θ
=
∠
P
\theta = \angle P
θ
=
∠
P
. Another acute angle
ϕ
\phi
ϕ
is such that
cos
ϕ
=
sin
θ
\cos \phi = \sin \theta
cos
ϕ
=
sin
θ
. a. (i) Calculate
sin
θ
\sin \theta
sin
θ
,
cos
θ
\cos \theta
cos
θ
and
tan
θ
\tan \theta
tan
θ
. b. (ii) Find
sin
ϕ
\sin \phi
sin
ϕ
and
tan
ϕ
\tan \phi
tan
ϕ
. c. (iii) Show that
tan
θ
×
tan
ϕ
=
1
\tan \theta \times \tan \phi = 1
tan
θ
×
tan
ϕ
=
1
.
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