Question
Question: If <img src="https://cdn.pureessence.tech/canvas_233.png?top_left_x=300&top_left_y=1375&width=300&he...
If then the arithmetic mean of f(x,y) and f(y,x) is.
A
x
B

C
0
D
1
Answer
0
Explanation
Solution
Let x+y=u,x−y=v
⇒ x=2u+v,y=2u−v,∴f(u,v)=(2u+v)⋅(2u−v)
Now,2f(x,y)+f(y,x)=2(2x+y⋅2x−y)+(2y+x⋅2y−x)=0.