Question

Evaluate the following definite integrals

Answer 1

\[\int\limits_{3}^{4}2\sin2x dx\]

Answer 2

wolframalpha.com

Answer 3

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

Answer 4

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

Answer 5

why?

Answer 6

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

Answer 7

did you have it in radians or degrees?

Answer 8

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

Answer 9

i got 1.10 radians
and .004 in degrees
your teacher made a mistake

Answer 10

yea... guessed as much lol.. >.< thanks though :D (currently writing cheat sheet for exam tomorrow) >.<