If f(x+ay,x-ay)=axy,then f(x,y)is equal to
xy
x-2a2y2
x2-y24
x2-y2a2
Given
f(x+ay,x-ay)=axy
Let x+ay=t……(i)
and x-ay=u……(ii)
On solving i & ii we get
x=t+u2 and y=t-u2a∴f(t,u)=at+u2*(t-u2a)
⇒f(t,u)=t2-u24
∴f(x,y)=x2-y24