is it true that if you are using u substitution and you change the boundaries, you don't need to change back to what you were subbing u with originally?

Question

anonymous · Answer

Yes :), if you leave the bounds you must plug back what you substituted, also this is why we do it for the indefinite integral.

butterflydreamer · Answer

ahhh, makes so much more sense now! xD Thanks!
I didn't realise that until today -_-... 
So it's probably best to change the boundaries at the beginning right? This way it's less complication and you don't need to change it back? :)

butterflydreamer · Answer

*less complicated

anonymous · Answer

Whichever way you feel comfortable, though Newton would have probably done it the differential way ;)

butterflydreamer · Answer

trrruuueee hahaha xD
But thanks for the clarification! :P