If A=[x:f(x)=0] and B=[x:g(x)=0] then A∩B will be
[f(x)]2+[g(x)]2=0
f(x)g(x)
g(x)f(x)
None of these
A∩B={x:x∈A and x∈B} =[x:f(x)=0 and g(x)=0]=[f(x)]2+[g(x)]2=0