Quick Question (Epsilon/Delta Limit Proofs)

Thread starter amd123
Start date Jan 22, 2011
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Limit Proofs

Jan 22, 2011

amd123

Homework Statement

[PLAIN]http://img641.imageshack.us/img641/2494/mathg.png
I've worked through it and at the 1st step I get:
(1/-e+1)<x<(1/e+1)

How do they have
(1/e+1)<x<(1/-e+1)?

Do you switch the signs of an inequality when you take the inverse of both sides?

Last edited by a moderator: May 5, 2017

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Jan 22, 2011

Dick

Science Advisor

Homework Helper

1<2. 1/1>1/2. Yes, you do reverse the inequalities when you invert.

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