integrate e^y? (1 Viewer)

[akuchan]

(a)find area between curve y = lnx, x axis, x =2, and x = 4
it said use simpsons rule, which i got 2.16 and is right
(b)then it says change subject of y = lnx to x, which is x = e^y
(c)and 'Hence find the exact area of part (a) '
i integrated lnx to get xlnx - x... but im suppose to use x = e^y i think, how?

 

[ssglain]

How did you integrate lnx without using IBP?

 

[kokodamonkey]

log rule.... ln x = y.... loge x = y.. (log based e). e^y = x.