Types of functions

Question

if f:x->y where x={x1,x2,x3,x4} and y= {y1,y2,y3,y4}defined by f={(x1,y3),(x2,y3),(x3,y1),(x4,y4)}. Determine is type of function bijective, surjective or injective and state whether it has inverse?

Answer 1

Neither injective nor surjective (therefore, not bijective and has no inverse).