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

Differential Calculus

New kid on the Block

Joined:	12 Sep 2007
Post:	22

13 Sep 2007 09:45:30 IST

0 People liked this

391

Why we get different limits by different methods??

None

Why we get different limits by different methods??

Share this article on:

Comments (7)

Anshuman Johri

Blazing goIITian

Joined: 27 Jan 2007

Posts: 559

13 Sep 2007 09:51:04 IST

Like 0 people liked this

who says that we get different limits by different methods?????
give an example

Priyesh

Blazing goIITian

Joined: 18 Feb 2007

Posts: 1042

13 Sep 2007 09:53:17 IST

Like 0 people liked this

yes who says that

the limits value should be same by all methods the graph of a function will tend to a specific value

Kaushik Chitragar

New kid on the Block

Joined: 12 Sep 2007

Posts: 22

13 Sep 2007 11:08:43 IST

Like 0 people liked this

for eg.....

f(x) = (x^2-6x+8)/x-2

_{[x ]}_{[ 2]}

Actual answer is (-2)

here if u take it by substitution u ll get 0/0 as the limit

its just a hopeless answer so i aksed that question

Anshuman Johri

Blazing goIITian

Joined: 27 Jan 2007

Posts: 559

13 Sep 2007 12:15:18 IST

Like 0 people liked this

if that is the case then what i can say is that u have not understood the concept of limits.

in the given example x tends to 2 and does not attain the value 2. 2 is not even in the domain of f(x).

limit x-->a of the function f(x) is the approximate value of the function in its neighborhood of x=a.

here
f(x)=(x-4)(x-2)/(x-2)
as x!=2 (!= means not equal to)
f(x)=x- 4 for all x !=2

so lim x-->2 f(x) = 2-4= -2

Kaushik Chitragar

New kid on the Block

Joined: 12 Sep 2007

Posts: 22

13 Sep 2007 18:14:54 IST

Like 0 people liked this

Thats what i told u we dont get the limit as -2 hen we do substitution man......

U got it by factorisation

my question is why dont we get same answer by both methods??

Neeraj Agarwal

Blazing goIITian

Joined: 22 Jan 2007

Posts: 2039

13 Sep 2007 18:22:14 IST

Like 0 people liked this

we say that 0/0 is an indeterminate form....i.e. we can't say anything about the function until we simplify it.....

so on simplifying we get the actual answer....and that answer u can get from any method....and it will be same

anish phophaliya

New kid on the Block

Joined: 10 Aug 2007

Posts: 28

13 Sep 2007 22:34:51 IST

Like 0 people liked this

its awfully foolish to say that you can find different anwsers to well defined problems.its just silly mistakes that makes you think that there are multiple answers to various questions

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