Trigonometric Equations

Exercise 5.5

1. (a) Define trigonometric equation with example. Solution: An equation involving trigonometric ratios is called trigonometric equation. For example: (i) (ii) (b) What do you mean by root (solution) of the given trigonometric equation? Solution: The value of an unknown angle which satisfies the given trigonometric equation is known as its root or solution. 2. (a) If , what is the least positive angle in quadrant. Solution: In first quadrant all the trigonometric ratios are positive, so there is not any angle in the first quadrant that satisfies . 2. (b) How to find the angle in quadrant, if the least positive angle is given. Solution: If the least positive angle is given, then the angle in quadrant 2. (c) What are the minimum and maximum values of and Solution: The minimum value of and The maximum values of and 3. Solve: (a) Solution: (b) Solution: (c) Solution: (d) Solution: (e) Solution: (f ) Solution: (g) Solution: (h) Solution: 4. Solve: (a) Solution: (b) Solution: (c) Solution: (d) Solution: (e) Solution: (f) Solution: 5. (a) Solve: Solution: Now, 5. (b) Solve: Solution: Now, 5. (c) Solve: Solution: Now, 5. (d) Solve: Solution: Now, 5. (e) Solve: Solution: Now, 5. (f) Solve: Solution: 6. (a) Solve: Solution: Now, 6. (b) Solve: Solution: Now, 6. (c) Solve: Solution: Now, 6. (d) Solve: Solution: 6. (e) Solve: Solution: Now, 6. (f) Solve: Solution: Now, 6. (g) Solve: Solution: 6. (h) Solve: Solution: 7. Solve:- (a) Solution: 7. Solve:- (b) Solution: 7. Solve:- (c) 7. Solve:- (d) Solution: 7. Solve:- (e) Solution: 7. Solve:- (f) Solution: 7. Solve:- (g) Solution: 7. Solve:- (h) Solution: 7. Solve:- (i) Solution: 7. Solve:- (j) Solution: 8. Solve:- (a) Solution: 8. Solve:- (b) Solution: 8. Solve:- (c) Solution: 8. Solve:- (d) Solution: 8. Solve:- (e) Solution: 8. Solve:- (f) Solution: 8. Solve:- (g) Solution: 8. Solve:- (h) Solution: 8. Solve:- (i) Solution: 9. Solve:- (a) Solution: 9. Solve:- (b) Solution: 9. Solve:- (c) Solution: 9. Solve:- (d) Solution: 9. Solve:- (e) Solution: 9. Solve:- (f) Solution: 9. Solve:- (g) Solution: 10. Solve: Solution: 11. (a) If , find the minimum value of . Solution: (b) , find . Solution: