Area for part II is 0.5 times (a - 1) times (ae^a - e^a) since (e^a - ae^a) is the y-coordinate of R which is negative, so we must make it positive first.

Area of I is 1/2 x 1 x e^a, not 1/2 x 1 x a, since the y-coordinate of P is e^a, not a.

Thks Bro!For part II,completely forgotten that y-coordinate of R is negative,thks for reminding!As for part I,I have accidentlly taken the x-coordinate of P instead of the y-coordinate of P,thks for pointing out!Cheers!