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I am not sure how to slove

I am not sure how to slove-example-1

1 Answer

1 vote

First .... the limit of the given function is NOT EQUAL to 5 (it diverges so it has no limit). There is a typo. The 14 should be positive.


\lim_(x \to\ 7) \bigg((x^2-9x+14)/(x-7)\bigg)=5

The precise definition of a limit is:


\text{If for every } \epsilon>0\text{ there exists a }\delta >0\text{ such that}\\|f(x)-L|<\epsilon\ \text{whenever }|x-a|<\delta

Given:


f(x) = (x^2-9x+14)/(x-7)\\\\L=5\\\\a=7\\\\\\|f(x)-L|<\epsilon\qquad \qquad \text{whenever}\quad |x-a|<\delta\\\\\bigg|(x^2-9x+14)/(x-7)-5\bigg|<\epsilon\qquad \text{whenever}\quad |x-7|<\delta\\\\\\\bigg|((x-2)(x-7))/(x-7)-5\bigg|<\epsilon\qquad \text{whenever}\quad |x-7|<\delta\\\\\\|x-2-5|<\epsilon\qquad \qquad \quad \text{whenever}\quad |x-7|<\delta\\\\|x-7|<\epsilon\qquad \qquad \text{whenever}\quad |x-7|<\delta


\epsilon = \delta

When ε = 0.1, δ = 0.1

When ε = 0.01, δ = 0.01

User Meeka
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