Home » Ask & Discuss » Mathematics. » Differential Calculus « Back to Discussion

Differential Calculus

Forum Expert

Joined:	28 Feb 2007
Post:	2173

16 Mar 2008 21:41:00 IST

0 People liked this

1284

Basics-Derivatives

None

Qn intended for all except sboosy:

For what n is the nth derivative of sin(x³) non-zero?

Share this article on:

Comments (33)

Go to Page...

gokul subramanian

Blazing goIITian

Joined: 28 Jan 2008

Posts: 1451

16 Mar 2008 21:46:00 IST

Like 0 people liked this

edited

gokul subramanian

Blazing goIITian

Joined: 28 Jan 2008

Posts: 1451

16 Mar 2008 21:50:14 IST

Like 0 people liked this

n=3

Anand Hegde

Blazing goIITian

Joined: 12 Jun 2007

Posts: 1078

16 Mar 2008 21:52:12 IST

Like 0 people liked this

is it n=3?.....just a guess Razz

Anand Hegde

Blazing goIITian

Joined: 12 Jun 2007

Posts: 1078

16 Mar 2008 21:54:18 IST

Like 0 people liked this

i think $f^{III}(0) = 6$

Sairam

Blazing goIITian

Joined: 14 Sep 2007

Posts: 573

16 Mar 2008 21:55:25 IST

Like 0 people liked this

n=3
edited :gokul--doesn series expansion workout more simpler??

gokul subramanian

Blazing goIITian

Joined: 28 Jan 2008

Posts: 1451

16 Mar 2008 21:55:55 IST

Like 0 people liked this

diff once u get cos(x^3)*3x^2
now on further diff u need to bother only abt the part of diff of the 'x^2' term as diff of other term only inc the power of x..so the imp term is 6xcos(x^3)
in the next diff the imp term is 6(x^3) which will b non 0 n other terms 0..
i am assuming u mean fⁿ(0)

sandeep ramesh

Blazing goIITian

Joined: 13 Mar 2008

Posts: 1183

16 Mar 2008 21:58:43 IST

Like 0 people liked this

was that for f^n(0)?

If it is so i think n=3 satisfies.

Sairam

Blazing goIITian

Joined: 14 Sep 2007

Posts: 573

16 Mar 2008 22:01:21 IST

Like 0 people liked this

Im sure u din give dis for differentiatin just like dat?
Taylor's series? the 1 u introduced after that (x^n-1)^n problem

Hari Shankar

Forum Expert

Joined: 28 Feb 2007

Posts: 2173

16 Mar 2008 22:03:03 IST

Like 0 people liked this

no counter questions!

Sairam

Blazing goIITian

Joined: 14 Sep 2007

Posts: 573

16 Mar 2008 22:05:48 IST

Like 0 people liked this

smple
just series expansion
bt y not sboosy??

Hari Shankar

Forum Expert

Joined: 28 Feb 2007

Posts: 2173

16 Mar 2008 22:17:23 IST

Like 0 people liked this

i discussed with him already.

now that u know my innermost secrets, cud you post the solution please.

Abhijith

Blazing goIITian

Joined: 23 Jan 2007

Posts: 678

16 Mar 2008 22:20:01 IST

Like 0 people liked this

maybe i lost my head today...but how are all of u saying it is 3????

He hasnt mentioned at what 'x' the nth derivative is 0.

sir, do you mean "For what 'n' is the nth derivate of sin(x^3) non zero for any value of 'x' or ?"

gokul subramanian

Blazing goIITian

Joined: 28 Jan 2008

Posts: 1451

16 Mar 2008 22:20:56 IST

Like 0 people liked this

yeah thts y i wrote the assumption

Abhijith

Blazing goIITian

Joined: 23 Jan 2007

Posts: 678

16 Mar 2008 22:21:35 IST

Like 0 people liked this

pretty big assumption buddy..

Hari Shankar

Forum Expert

Joined: 28 Feb 2007

Posts: 2173

16 Mar 2008 22:22:03 IST

Like 0 people liked this

good lord missed that. yeah i am asking at the point x=0. sorry fellas, just boink me to make me feel better

gokul subramanian

Blazing goIITian

Joined: 28 Jan 2008

Posts: 1451

16 Mar 2008 22:23:02 IST

Like 0 people liked this

no koni...but my assumption comes after some very hard thinking n c it turned out to be rite!

sandeep ramesh

Blazing goIITian

Joined: 13 Mar 2008

Posts: 1183

16 Mar 2008 22:23:53 IST

Like 0 people liked this

could you even give the reason for the boink? That would make our job simpler Rotfl

Anand Hegde

Blazing goIITian

Joined: 12 Jun 2007

Posts: 1078

16 Mar 2008 22:25:31 IST

Like 0 people liked this

lol

sandeep ramesh

Blazing goIITian

Joined: 13 Mar 2008

Posts: 1183

16 Mar 2008 22:27:30 IST

Like 0 people liked this

so why isnt 3 right?

Quick Reply

Reply

	Some HTML allowed.
	Keep your comments above the belt or risk having them deleted.
	Signup for a avatar to have your pictures show up by your comment
	If Members see a thread that violates the Posting Rules, bring it to the attention of the Moderator Team