Saved Bookmarks
| 1. |
prove that 3 cos^(-1) x = cos^(-1) (4x^3 - 3x), x in [1/2,1] |
|
Answer» Solution :PUT `COS^(-1) x = y.` Then cos y = x `therefore 4x^3 - 3X = 4 cos^3 y - 3 cos y = cos 3y` `IMPLIES 3y = cos^(-1) (4x^3 - 3x)` `implies 3 cos^(-1) x = (4x^3 - 3x)` |
|