ICSE Worksheet for chapter-3 Trigonometry class 9

ICSE Worksheet for chapter-3 Trigonometry class 9

Worksheet For class 9

Physics Wallah Solutions are considered very useful when preparing for the ICSE Class 9 Maths exams. Here, we bring you the Worksheet Solutions for Class 9 Maths, providing detailed explanations of the questions in Trigonometry exercises. The subject matter experts of Physics Wallah have devised these answers as per the syllabus prescribed by the ICSE.

Physics Wallah has provided the complete solutions of Class 9 Maths Worksheet - 3 Trigonometry in PDF format. You can avail these solutions and download them for free to practice them offline. For other ICSE Worksheets for class 9 Maths , check out the main page of Physics Wallah.

Questions

Q1. If tan⁡ θ= a/b then value of is (a sinθ+b cosθ)/(a sinθ-bcosθ)=

1. (a ² +b ² )/(a ² -b ² )
2. (a ² -b ² )/(a ² +b ² )
3. a/√(a ² +b ² )
4. 1/√(a ² +b ² )

Q2. The value of the expression 4/3 cot ² 30 ⁰ + 3sin ² 30 ⁰ -2cosec ² 60 ⁰ - 3/4 tan ² 30 ⁰ is

1. 1
2. (-20)/3
3. 10/3
4. 5

Q3. The value of the expression(5 sin ² 30 ⁰ +cos ² 45 ⁰ +4tan ² 60 ⁰ )/(2sin30 ⁰ cos60 ⁰ +tan45 ⁰ ) is

1. 4
2. 9
3. 53/12
4. 55/6

Q4. The value of tan 5 ⁰ tan 10 ⁰ tan 15 ⁰ tan 20 ⁰ ……… tan 85 ⁰ is

1. 1
2. 2
3. 3
4. None of these

Q5. If α+β = and sin α = then sin β is

1. √2/3
2. 2√2/3
3. 2/3
4. 3/4

Q6. If 7sinα =24 cos α; 0 < α < π/2,then value of 14 tan α -75 cos α-7sec α is equal to

1. 1
2. 2
3. 3
4. 4

Q7. If tan θ =4, then (tan⁡θ/((sin ³ θ)/cosθ+sinθcosθ))is equal to

1. 0
2. 2
3. 2√2
4. 1

Q8. The area of the triangle is 12 sq.cm Two sides are 6 cm and 12cm. The included angle is:

1. cos ^-1 (1/3)
2. cos ^-1 (1/6)
3. sin ^-1 (1/6)
4. sin ^-1 (1/3)

Q9. An aero plane when flying at a height 2500 m from the ground passes vertically above another aero plane. At an instant when the angles of elevation of the two aero planes from the same point on the ground are 45 ⁰ ,and 30 ⁰ respectively. Then the vertical distance between the two aero planes at the instant is

1. 1158 m
2. 1058 m
3. 1008 m
4. None

Q10. The shadow of a tower is 30 m when sun’s altitude is 30 ⁰ . When the sun’s altitude is 60 ⁰ , then the length of the shadow will be

1. 60 m
2. 15 m
3. 10 m
4. 5 m

Q11. The angle of elevation of a cloud from a point 200 m above a lake is 30 ⁰ and the angle of depression of its reflection in the lake is 60 ⁰ , then the height of the cloud (in m) above the lake is

1. 200
2. 300
3. 400
4. None

Q12. The angle of elevation of the top of a vertical tower from two points 30 m apart and on the same straight line passing through the base of the tower are 30 ⁰ and 60 ⁰ respectively. The height of the tower is

1. 10 m
2. 15 m
3. 12m
4. 30 m

Q13. The angle of elevation of the top of tower from the top and bottom of the building h meter high are α and β then the height of the tower is

1. h sin α cos β/ sin (α+β)
2. h cos α cos β /sin (β-α)
3. h cos α sin β/sin (β-α)
4. None of these

Q14. When a eucalyptus tree is broken by a strong wind, its top strikes the ground at an angle of 30 ⁰ to the ground and at a distance of 15m foot. What is the height of the tree?

1. 15 m
2. 10 √3
3. 20 m
4. 10 m

Q15. A man at the top of the vertical light house observes a boat coming directly towards it. If it takes 20 minutes for the angle of depression to change from 30 ⁰ to 60 ⁰ the time taken by the boat to reach the lighthouse from the point when the angle of depression was 30 ⁰ is

1. 30 min
2. 20 min
3. 10 min
4. 5 min

Q16. The expression (1- tan A + sec A)(1 –cot A+ cosec A) has value

1. -1
2. 0
3. 1
4. 2

Q17. (1 +tan ² θ)/(1+ cot ² θ)=

1. tan ² θ
2. cot ² θ
3. sec ² θ
4. cosec ² θ

Q18. The tops of the two poles of heights 20m and 14 m are connected by a wire making an angle of 30 ⁰ with the horizontal, then the length of the wire is

1. 40 m
2. 12 m
3. 28m
4. 68 m

Solutions

1. 1
2. 3
3. 4
4. 1
5. 2
6. 2
7. 4
8. 4
9. 2
10. 3
11. 3
12. 3
13. 4
14. 1
15. 1
16. 4
17. 1
18. 2