Mathematics
OpenStudy (anonymous):

Evaluate the following definite integrals

OpenStudy (anonymous):

$\int\limits_{3}^{4}2\sin2x dx$

OpenStudy (anonymous):

wolframalpha.com

myininaya (myininaya):

u=2x du=2dx if x=4, u=8 if x=3, u=6 $\int\limits_{6}^{8}sinu du=-cosu|=-\cos8+\cos6$

OpenStudy (anonymous):

yea thats what i got... my teacher must have put something in incorrectly...

myininaya (myininaya):

why?

OpenStudy (anonymous):

i dunno... ive done it like 10 times and i keep getting 1.11 (same as my tutor) but Lecturer got 0.88 :S:S:S

myininaya (myininaya):

did you have it in radians or degrees?

OpenStudy (anonymous):

radians and degrees gegrees i got .81 or something like that but not .88

myininaya (myininaya):