Prove that:
(aSinA+bCosA)^2+(aCosA-b SinA)^2=a^2+b^2
Answers
Answered by
5
Answer:
hope it helps......................
Attachments:
Answered by
3
Step-by-step explanation:
R.T.P : (aSinA + bCosA)² + (aCosA - bSinA)² = a² + b²
= (a²Sin²A + b²Cos²A + 2abSinACosA) + (a²Cos²A + b²Sin²A - 2abSinACosA)
(by using algebraic identity (a + b)²)
= a²Sin²A + a²Cos²A + b²Sin²A + b²Cos²A + 2abSinACosA - 2abSinACosA
= a²(Sin²A + Cos²A) + b²(Sin²A + Cos²A)
= a² + b² (Sin²A + Cos²A = 1)
Similar questions