f :[a, b] → [5, 6] be defined as y = f(x) = 2x³ - 9x² +12x + 1
Then which of the following is/are true?

Maximum value of a for y = f(x) to be a one-one function is 2

Minimum value of b for y = f(x) to be an onto function is 1.

Minimum value of a for y = f(x) to be a one-one function is 1/2

Maximum value of b for y = f(x) to be an onto function is 5/2