Model Question Paper
Trigonometry - Part IV
10th Standard
Maths Reg.No. :
I.Answer all the questions.
II.Use blue pen only.
III.Question number 16 is compulsory.
Time : 01:00:00 Hrs Total Marks : 40
Part-A 5x1=5
1) 2
(1 + cot θ) (1 − cosθ) (1 + cosθ) =
(a) 2
tan θ − sec θ
2
(b) 2
sin θ − cos θ
2
(c) 2
sec θ − tan θ
2
(d) 2
cos θ − sin θ
2
2) 2
(cos θ − 1) (cot θ + 1) + 1 =
2
(a) 1 (b) -1 (c) 2 (d) 0
2
3) 1+tan θ
2
=
1+cot θ
(a) cos θ
2
(b) tan θ
2
(c) sin θ
2
(d) cot θ
2
4) 2
sin θ +
1
2
=
1+tan θ
(a) cosec θ + cot θ
2 2
(b) 2
cosec θ − cot θ
2
(c) 2
cot θ − cosec θ
2
(d) 2
sin θ − cos θ
2
5) 2
9tan θ − 9sec θ =
2
(a) 1 (b) 0 (c) 9 (d) -9
Part-B 5 x 2 = 10
6) Prove the following identities sin θ
= cosec θ + cot θ
1−cos θ
−−−−−
7) Prove the following identities √ 1−sin θ
= sec θ − tan θ
1+sin θ
8) Prove the following identities cos θ
= 1 + sin θ
secθ−tan θ
−−−− −− −−−− −− −
9) Prove the following identities √ sec 2 2
θ + cosec θ = tan θ + cot θ
2
10) Prove the following identities 1+cos θ−sin θ
= cotθ
sin θ (1+cos θ)
Part-C 5 x 5 = 25
11) Prove the following identities. (1 + cot θ − cosec θ)(1 + tanθ + sec θ) = 2
12) Prove the following identities.
sin θ−cos θ+1 1
=
sin θ+cos θ−1 sec θ−tan θ
∘
13) Prove the following identities. tan θ
=
sin θsin(90 −θ)
∘
2 2
1−tan θ 2sin (90 − θ)−1
14) Prove the following identities. 1
−
1
=
1
−
1
cosec θ−cot θ sin θ sin θ cosec θ+cot θ
2 2
15) a) Prove the following identities.
cot θ+sec θ
2 2
= (sin θ cos θ)(tan θ + cotθ)
tan θ+cosec θ
(OR)
b) Prove the following identities. tan θ
+
cot θ
= 1 + sec θ cosec θ
1−cot θ 1−tan θ
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