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it's professional math.

2007-02-01 01:51:53 · 6 answers · asked by moji 1 in Science & Mathematics Mathematics

6 answers

limit sin(x-1)\x^2-1 as x->1

Use L'Hospital theorem

limit f(x)/g(x) = limit f'(x)/g'(x)

Here

limit sin(x-1)\(x^2-1) =
limit cos(x-1)/(2x) = 1/2

2007-02-01 02:08:49 · answer #1 · answered by catarthur 6 · 1 0

lim [ sin(x - 1) / (x^2 - 1) ]
x -> 1

That's what I'm assuming you mean (because that's the only way this question's answer is nontrivial.

To solve this, note that if we plug in x = 1, we will obtain the form
[0/0]. Therefore, one option is to use L'Hospital's rule. This involves taking the derivative of the top and bottom, and finding this new limit. Doing so, we get

lim [ cos(x - 1) / 2x ]
x -> 1

Plugging x = 1 into this limit, we get

cos(1 - 1) / 2(1) = cos(0) / 2 = 1/2

2007-02-01 02:10:04 · answer #2 · answered by Puggy 7 · 0 0

A=sin(x-1)/(x^2-1)

(x^2-1)=(x-1)(x+1)

=>A=sin(x-1)/{(x-1)(x+1)}={sin(x-1)/(x-1)}{1/(x+1)}

put z=x-1=> x=z+1

=> => A={sinz/z}/(z+2)

i think that you are looking for the lim -->0


lim(sinz/z)=1

limA=1/(0+2)=>
=> limA=1/2


ok?

2007-02-01 02:09:19 · answer #3 · answered by Anonymous · 0 0

x^2 -1 = (x+1)*(x-1)

When x→1
Lt sin (x-1) / ( x^2 -1)

= Lt sin (x-1) / (x+1)*(x-1)

=Lt 1/ (x+1)* Lt sin (x-1) / (x-1)

=Lt 1/ (x+1) * 1 = ½.

2007-02-01 02:05:42 · answer #4 · answered by Pearlsawme 7 · 1 0

As x approaches what?

2007-02-01 01:55:14 · answer #5 · answered by Chris S 5 · 1 0

uh...

2007-02-01 01:59:15 · answer #6 · answered by Joe the God of Averageness® 4 · 0 0

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