InterviewSolution
Saved Bookmarks
| 1. |
If x = sin14x + cos20 x, then write the smallest interval in which the value of x lie. |
|
Answer» We know the range of sin x is -1 ≤ sin x ≤ 1 ∴ 0 ≤ sin 14x ≤ 1 We know the range of cos x is -1 ≤ cos x ≤ 1 ∴ 0 ≤ cos 20x ≤ 1 0 < sin14x + cos20x ≤ 2 which means that the value of x lies in the interval [0,2] But there's a problem, when sine is 0 cosine is 1, they might even be 0 and -1 at particular points (not in this case, since they are even powers), so the minimum we would get should be more than 0. Hence the value of x lies in (0,1] |
|