Question

Let f = {(x, y) |x,y; ∈ N and y = 2x} be a relation on N. Find the domain, co-domain and range. Is this relation a function?

Answer 1

X = {1,2,3,...} 

Y = {1,2,3,...} 

f = {(1,2) (2, 4) (3, 6) (4, 8) ...} 

Domain = {1, 2, 3, 4 …} 

Co – Domain = {1, 2, 3, 4 ...} 

Range = {2, 4, 6, 8 } 

Yes this relation is a function.