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Trigonometry Ratio of Complementary Angles

Trigonometry Ratio of Complementary Angles

Let us consider a triangle ABC right angled at B. Let

Example 6. Without using trigonometirc tables, evaluate:

Solution:-

= -6

 Example 7. Evaluate:

Solution:-

Example 8. Evaluate:

Solution:-

= 0

 

Exercise - 25

Evaluate the following:

1.

2. Sec 500 Sin 400 + Cos 400 Cosec 500

3.

4.

5.

6.

7.

8.

9.

10. tan 350 tan 400 tan 450 tan 500 tan 550

11. tan 70 tan 230 tan 600 tan 670 tan 830

12. tan 50 tan 250 tan 300 tan 650 tan 850

13.

14.

15.

16.

17.

18.

19. Express sin 810 + tan 710 in terms of trigonometric ratios of angles between 00 and 450.

20. Express cos 750 + cot 750 in terms of trigonometric ratios of angles between 00 and 450.

21. If where are acute angles, find the value of

22. If A and B are acute angles and sin A = cos B, Prove that A + B = 900.

23. If A, B, C are the interior angles of a triangle ABC, show that show that

24.

25.

26.

Answers

1. 0

2. 2

3. 2

4. 0

5. 0

6. 0

7. 1/2

8. 1

9. 1

10. 1

11.

12.

13. 0

14. 2

15. 1

16. 2

17. 2

18. 2

19. cos 90 + cot 190

20. sin 15 0 + tan 15 0

21. 280

 

 

 


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