Please help me to solve this integration problem... And i need some advice too


tbh when it comes to calculus i was smartest guy in my campus of 400 but after a break of 3 months , i don't remember anything. i have solved questions like this in minutes and sometimes in seconds but i was unable to remember proper method. i had an entrance exam on 15 where too many integration questions were asked and i was sitting blank. Now I'm preparing for another entrance exam on 10th may and i gotta get my skills back before 10th may. what should i do and where should i start... please help


it was a definite integral problem but i dont remember upper and lower limits... maybe I'll have to wail till they make that question paper public