If f:A → B and g:B → C are onto, then gof:A → C is _________.

Let f:{2, 3, 4, 5} → {3, 4, 5, 9} and g = {3, 4, 5, 9} → {7, 11, 15} be functions defined as f(2) = 3, f(3) = 4, f(4) = f(5) = 5 and g(3) = g(4) = 7 and g(5) = g(11) = 11
Find gof(4)

Let A= {a,b,c} and B= {1,2}. Consider the relation R defined from set A to set B. Then R is equal to set 

The function f:R → R given by f(x) = 2x is

If f:R → R is defined by f(x) = x² - 3x + 2 then f(f (x)) = _______.

If f(x) = e^x and g(x) = log x(x > 0), then

The relation 'is parallel to' on the set A of all coplanar straight line is an __________ relation.