Saved Bookmarks
| 1. |
( \operatorname { sin } 3 x + \operatorname { sin } x ) \operatorname { sin } x + ( \operatorname { cos } 3 x - \operatorname { cos } x ) \operatorname { cos } x = 0 |
|
Answer» LHS = (sin3x+sinx)sinx + (cos3x-cosx)cosx = (2sin2xcosx)sinx + (2sin2x(-sinx))cosx = 2sin2xcosxsinx -2sin2xcosxsinx =0 =RHS |
|