Sujeet Kumar

Question 1.Find the values of: Question 2. Question 3. v. tan x + cot x = 2 cosec 2xSolution:L.H.S. = tan x + cot x Solution: Solution:= 2 cos x= R.H.S.[Note : The question has been modified.] viii. 16 sin θ cos θ cos 2θ cos 4θ cos 8θ = sin 16θSolution:L.H.S. = 16 sin … Read more

Question 1.Find the values of:i. sin 690°ii. sin 495°iii. cos 315°iv. cos 600°v. tan 225°vi. tan (- 690°)vii. sec 240°viii. sec (- 855°)ix. cosec 780°x. cot (-1110°)Solution:i. sin 690° = sin (720° -30°)Solution:i. sin 690° = sin (720° -30°)= sin (2 x 360° – 30°)= – sin 30°= -1/2 ii. sin 495° = sin (360° + … Read more

Question 1.Find the values of:i. sin 150°ü. cos 75°iii. tan 105°iv. cot 225°Solution:i. sin 15° = sin (45° – 30°)= sin 45° cos 30° – cos 45° sin 30° ii. cos 75° = cos (45° + 30°)= cos 45° cos 30° – sin 45° sin 30° iii. tan 105° = tan (60° +45°) iv. cot … Read more

I. Select the correct option from the given alternatives. Question 1.The value of the expressioncos1°. cos2°. cos3° … cos 179° =(A) -1(B) 0 (D) 1Answer:(B) 0 Explanation:cos 1° cos 2° cos 3° … cos 179°= cos 1° cos 2° cos 3° … cos 90°… cos 179°= 0 …[∵ cos 90° = 0] Question 2.(A) 2cosec … Read more

Question 1. A lies in the 2nd quadrant.We know that,B lies in the 4th quadrant, Question 2.If and A, B are angles in the second quadran, then prove that 4cosA + 3 cos B = -5Solution:Since B lies in the second quadrant, cos B < 0 Question 3. Solution: Question 4.Eliminate 0 from the following:i. x … Read more

Question 1.Find the trigonometric functions of 0°, 30°, 45°, 60°, 150°, 180°, 210°, 300°, 330°, – 30°, – 45°, – 60°, – 90°, – 120°, – 225°, – 240°, – 270°, – 315°Solution:Angle of measure 0°: Let m∠XOA = 0° = 0cIts terminal arm (ray OA) intersects the standardunit circle in P(1, 0).Hence,x = 1 … Read more

I. Select the correct option from the given alternatives. Question 1. (A) 246°(B) 264°(C) 224°(D) 426°Answer:(B) 264° Question 2.156° is equal to Answer:(B) Question 3.A horse is tied to a post by a rope. If the horse moves along a circular path, always keeping the rope tight and describes 88 metres when it traces the … Read more

Question 1.Find the length of an arc of a circle which subtends an angle of 108° at the centre, if the radius of the circle is 15 cm.Solution:Here, r = 15cm and = 9π cm. Question 2.The radius of a circle is 9 cm. Find the length of an arc of this circle which cuts … Read more

Question 1.(A) Determine which of the following pairs of angles are co-terminal.i. 210°, 150°ii. 360°, -30°iii. -180°, 540°iv. -405°, 675°v. 860°, 580°vi. 900°, -900°Solution:210°,- 150°210°-(- 150°) = 210°+ 150°= 360°= 1 (360°),which is a multiple of 360°.∴ The given pair of angles is co-terminal. ii. 360°, – 30°360° – (- 30°) = 360° + 30°= … Read more

1A. Answer in One Sentence: Question 1.What is Journal?Answer:Journal is a book of account in which all types of day-to-day business transactions are recorded in chronologicalorder. Question 2.What is Narration?Answer:Explanation of transaction which is written just below the accounting entry in the particular column is called narration. Question 3.What is GST?Answer:GST is an abbreviated form … Read more