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#(i) sin 60° cos 30° sin 30° cos 60, (ii) 2 tan2 45° cos2 30° - sin2 60° (iii) "cos 45°" /"sec 30° cosec 30°" (iv) "sin 30° tan 45° - cosec 60°" /"sec 30° cos 60° cot 45°" (v) "5 cos260° 4sec230°-tan245°" /"sin230° cos230°"

#Class 10, important formula for ex 8.2

#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 .

#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 ΔPQR, right-angled at Q, PR QR = 25 cm and PQ = 5 cm. Determine the values of sin P, cos P and tan P

Class 10 Ex 8 1 q.n. (8)If 3 cot A = 4, check whether (1−"tan2A" )/1" tan2A" = cos² A - sin² A or not

#Ex 8.1 Class 10 (7) If cot θ = 7/8, evaluate: (i) "(1 sinθ)(1−sinθ)" /"(1 cosθ)(1−cosθ)" (ii) cot²θ

#Class 10 Ex 8.1 (6) If ∠A and ∠B are acute angles such that cos A = cos B, then show that ∠A = ∠B

# Class 10 Ex 8.1 Q.N. (5)Given sec θ = 13/12 calculate all other trigonometric ratios.

#Class 10 Ex 8.1 (4) Given 15 cot A = 8, find sin A and sec A

#Ex 8.1 Q.N. (3) If sin A = 3/4 , calculate cos A and tan A

#2. In Fig. 8.13, find tan P - cot R

#Q.N. (1) In ∆ABC right angled at B, AB = 24 cm, BC = 7 cm. Determine:(i) sin A, cos A(ii) sin C, cos C