Question

If sin A+ cos A=√2,
find the value of
sin A. cos A.

Answer 1

Answer: The answer is 1/2.

Step-by-step explanation:

1. Square both sides. We get (sin A+ cos A)^2=2

2. Expand (sin A+ cos A)^2.

3. Then we obtain (sin A)^2+(cos A)^2+2sinAcosA = 2

4. Place (sin A)^2+(cos A)^2=1.

then 1+ 2sinAcosA= 2

then shift sides. I hope your confusion is cleared