The Student Room Group

FP3

http://mathsathawthorn.pbworks.com/f/FP3Jun06.pdf
q6a?
This is what i have done below:
r=sinh0
A=1/2 Integral r^2.dtheta
Therefore A=1/2 Integral sinh^2.dtheta
do i use sinh^2x=cosh^2x-1
Or sinh^x =1/2(cosh2x-1).dtheta
Like how am i supposed to know?
Reply 1
Original post by Ayaz789
http://mathsathawthorn.pbworks.com/f/FP3Jun06.pdf
q6a?
This is what i have done below:
r=sinh0
A=1/2 Integral r^2.dtheta
Therefore A=1/2 Integral sinh^2.dtheta
do i use sinh^2x=cosh^2x-1
Or sinh^x =1/2(cosh2x-1).dtheta
Like how am i supposed to know?


Which one will let you integrate it easily and which one won't?
Reply 2
Original post by Zacken
Which one will let you integrate it easily and which one won't?

Will they both work first of all? And 1/2 (cosh2x-1)
Reply 3
Original post by Ayaz789
Will they both work first of all? And 1/2 (cosh2x-1)


I don't see how integrating cosh^2 x is any easier than integrating sinh^2 x...
Reply 4
Original post by Zacken
I don't see how integrating cosh^2 x is any easier than integrating sinh^2 x...


Huh? Are you agreeing or disagreeing with me?
Reply 5
Original post by Ayaz789
Huh? Are you agreeing or disagreeing with me?


I agree that you should use 1/2(cosh 2x...). I don't see why you'd consider cosh^2 x - 1 an option though.
Reply 6
Original post by Zacken
I agree that you should use 1/2(cosh 2x...). I don't see why you'd consider cosh^2 x - 1 an option though.


Yep haha. If i did cosh^2x-1 can you please show me how i would do it?
Reply 7
Original post by Ayaz789
Yep haha. If i did cosh^2x-1 can you please show me how i would do it?


But that's what I'm saying, doing cosh^2 x - 1 is useless, you don't do it. If you wanted to, you could do cosh^2 x = 1/2(cosh 2x + 1) but... then that was a waste of your time since you might as well have used cosh 2x +... on sinh^2 x right away.
Reply 8
Original post by Zacken
But that's what I'm saying, doing cosh^2 x - 1 is useless, you don't do it. If you wanted to, you could do cosh^2 x = 1/2(cosh 2x + 1) but... then that was a waste of your time since you might as well have used cosh 2x +... on sinh^2 x right away.

Okay np
Reply 9
Original post by Ayaz789
Okay np


Okay? :tongue:
Reply 10
Original post by Zacken
Okay? :tongue:


I mean i understand haha
Reply 11
Original post by Ayaz789
I mean i understand haha


Oh, okay. Great.

Quick Reply

Latest