The statement:

If f(1)>0 and f(3)<0 then there exists a number c between 1 and 3 such that f(c)=0

is false but i dont understand why?

How can you tell when a root (c) will exist between the two given numbers to make f(c)=0?

thanks

chad

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- Sep 22nd 2009, 10:49 AMmybrohshi5IVT root question
The statement:

If f(1)>0 and f(3)<0 then there exists a number c between 1 and 3 such that f(c)=0

is false but i dont understand why?

How can you tell when a root (c) will exist between the two given numbers to make f(c)=0?

thanks

chad - Sep 22nd 2009, 11:53 AMCalculus26
whats missing is is that f(x) must be continuous.

If f is continuous and f(1) > 0 and f(3) < 0 then there is a c in (1,3)

st f(c) = 0