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View Full Version : continuity problem


Hygelac
Sep25-04, 02:25 PM
Hi, I have just one more problem :) here it is:

(because I don't know how to do theta, "@" will equal theta)

Find a value of K so that f(2) is continuous at @=0

( != means "not equal")

f(@) = ( (2sin@)/@ , @ !=0 )
( 5k , @=0 )

f(@) is a piecewise function

I don't know how to get started on this problem, any help would be much appreciated :)

vsage
Sep25-04, 02:34 PM
The simplest way would be to set 5k = lim(@->0)[2sin(@)/@]

Using l'hopital's rule, lim(@->0)[2sin(@)/@] = lim(@->0)[2cos(@)/1]

I think you can do the rest :)

Hygelac
Sep26-04, 05:08 PM
Whops, it shoudl be f(@) not f(2)

So,

5k = (2sin(@))/@

k = [(2sin(@))/@]/5

Would that work, or did I totally miss your point?

vsage
Sep26-04, 05:15 PM
Whops, it shoudl be f(@) not f(2)

So,

5k = (2sin(@))/@

k = [(2sin(@))/@]/5

Would that work, or did I totally miss your point?

I think you may have because that doesn't work. that function is not defined at @ = 0 so you have to use limits. k = 1/5 * limit[@->0](2sin(@)/@)