InterviewSolution
Saved Bookmarks
| 1. |
Find the value of (p + q)2, if p + q Cot3 α = Cot α.Cosec α and q = p tan α.1). 1 + Cos α2). 1 + Sin 2α3). 1 – cos 2α4). 1 - Sin α |
|
Answer» p + q COT3 α = Cot α.Cosec α ⇒ p + q COS3 α/Sin3 α = Cos α/Sin2 α Putting q = p TAN α in the equation we get ⇒ p + p tan α.(Cos3 α/Sin3 α) = Cos α/Sin2 α Putting tan α = sin α /cos α and simplifying we get ⇒ p(1 + Cos2 α/Sin2 α ) = Cos α/Sin2 α ⇒ p = Cos α Putting that in q = p tan α we get q = Sin α Here (p + q)2 = (Sin α + Cos α)2 Using (a + b)2 = a2 + b2 + 2AB we get (p + q)2 = Sin2 α + Cos2 α + 2 Sin α.Cos α Using Sin2 α + Cos2 α = 1 and 2 Sin α.Cos α = Sin 2α We get (p + q)2 = 1 + Sin 2α |
|