EduSahara™ Assignment
Name : Trigonometry Word Problems
Chapter : Trigonometrical Identities
Grade : ICSE Grade X
License : Non Commercial Use
Question
1
1.
In
△DEF
, right angled at
E
,
if
tan
D
=
1
5
,
find
sin
D
cos
F
+
cos
D
sin
F
(i)
5
26
√
26
(ii)
1
(iii)
1
26
√
26
(iv)
√
26
(v)
1
5
√
26
Question
2
2.
In
△MNO
, right angled at
N
,
if
tan
M
=
3
8
,
find
cos
M
cos
O
−
sin
M
sin
O
(i)
3
73
√
73
(ii)
1
3
√
73
(iii)
8
73
√
73
(iv)
0
(v)
1
8
√
73
Question
3
3.
Find the length of the side of a 9-sided regular polygon inscribed in a circle of radius 1 m
(i)
0.7840 m
(ii)
0.6840 m
(iii)
0.7340 m
(iv)
0.5840 m
Question
4
4.
Find the length of the chord of the unit circle subtending an angle of 120° at the centre
(i)
1.6320
(ii)
1.7320
(iii)
1.8320
(iv)
1.7820
Question
5
5.
Find the area of the right angled triangle with hypotenuse 5 cm and one of the acute angle being 58°
(i)
5.5971 cm
(ii)
4.5971 cm
(iii)
6.5971 cm
(iv)
7.5971 cm
Question
6
6.
Find the area of an isosceles triangle with base 8 cm and vertical angle 48°
(i)
36.9389 cm
(ii)
34.9389 cm
(iii)
37.9389 cm
(iv)
35.9389 cm
Question
7
7.
If
P
,
Q
and
R
are the interior angles of a triangle, then
sin
(
P + Q
2
)
=
(i)
sin
(
P
2
)
(ii)
cos
(
R
2
)
(iii)
sin
R
(iv)
sin
(
R
2
)
(v)
cos
(
P
2
)
Assignment Key
1) (ii)
2) (iv)
3) (ii)
4) (ii)
5) (i)
6) (iv)
7) (ii)
