Question
Simplify the following trigonometric expression:Â
8 cos 40° cosec 50° − 2 cot 30° cot 60°ÂSolution
8 cos 40° cosec 50° − 2 cot 30° cot 60°
= 8 cos 40° cosec (90° − 40°) − 2 cot 30° cot (90° − 30°)
Using, cosec (90° − A) = sec A and cot (90° − A) = tan A
= 8 cos 40° sec 40° − 2 cot 30° tan 30°
Since, sec A is reciprocal of cos A and cot A is reciprocal of tan A.
= 8 − 2 = 6
51, 60, 78, ?, 141, 186
3, 8, 18, 33, 53, ?
- 6, ?, 9816, 9825, 19429, 19438
84, 63, ?, 283.5, 1701
14, 20, 29, 44, 65, ?
3.6 × 1.5 + 8.4 × 2.5 – 9.2 × 3.5 = ? – 9.2 × 4.4
18Â Â Â 19Â Â Â 34Â Â Â 111Â Â Â Â 428Â Â Â Â 2165Â Â Â Â ?
...7, 8, 18, 57, 232, ?
What will come in place of the question mark (?) in the following series?
102, 111, 136, 185, 266, ?
10, 10, 15, 30, 75, ?