Question

*If sin A + cos A = 1, then value of sin 2A is:*

1️⃣ 1
2️⃣ 2
3️⃣ between 1 and 2
4️⃣ 0
Please tell me answer ​

Answer 1

Solution :-

=> sinA + cosA = 1

=> ( sinA + cosA )² = 1²

=> sin²A + cos² A + 2sinA.cosA = 1

=> 1 + 2sinA . cosA = 1

=> 2sinA . cosA = 1 - 1

=> 2sinA.cosA = 0

=> sin2A = 0

$\blue{\underbrace{\overbrace{\Huge\boxed{\red{\bf{\leadsto sin2A=0}}}}}}$

Answer 2

Answer:

The answer is a option B