Question

1. In  ABC, right-angled at B, AB = 24 cm, BC = 7 cm. Determine :

(i) sin A, cos A

(ii) sin C, cos C

2. In Fig. 8.13, find tan P – cot R.

3. If sin A =

3

,

4

calculate cos A and tan A.

4. Given 15 cot A = 8, find sin A and sec A.

5. Given sec  =

13

,

12 calculate all other trigonometric ratios.

6. If  A and  B are acute angles such that cos A = cos B, then show that  A =  B.

7. If cot  =

7

,

8

evaluate : (i) (1 sin )(1 sin )

,

(1 cos ) (1 cos )

   

   

(ii) cot2 

8. If 3 cot A = 4, check whether

2

2

1 tan A

1 + tan A



= cos2

A – sin2A or not.

9. In triangle ABC, right-angled at B, if tan A =

1

,

3

find the value of:

(i) sin A cos C + cos A sin C

(ii) cos A cos C – sin A sin C

10. In  PQR, right-angled at Q, PR + QR = 25 cm and PQ = 5 cm. Determine the values of

sin P, cos P and tan P.

11. State whether the following are true or false. Justify your answer.

(i) The value of tan A is always less than 1.

(ii) sec A =

12

5

for some value of angle A.

(iii) cos A is the abbreviation used for the cosecant of angle A.

(iv) cot A is the product of cot and A.

(v) sin  =

4

3

for some angle .​

Answer 1

Answer:

for some value of angle A.

(iii) cos A is the abbreviation used for the cosecant of angle A.

(iv) cot A is the product of cot and A.

(v) sin  =

4

3

for some angle .