In my self-study Calculus book I finished with the 'intuitive' definition of the limit and the text directed me to the 'formal' definition of the limit. After reading the section covering it a few times I think I comprehended the details of the rigorous rules dictating it - but obviously not well enough.(adsbygoogle = window.adsbygoogle || []).push({});

The problem is I'm having trouble proving limits for functions of the second order (I find the limit and prove it is so). For instance, the limit of 3x-1 as x approaches 2 is fairly trivial, but, say, the limit of (x^2) - 3 as x approaches 2 confuses me. I try to figure out a value to let epsilon = delta be, but get to the point where epsilon > |x-2||x+2|, and don't know how to 'make the connection' between it and delta > |x-2|, letting (epsilon)/|x+2| = delta doesn't seem right. If you could help me get my head around proving limits for these higher order functions, I'd really appreciate it. Thanks.

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# Epsilon-Delta Definition of Limit (Proofs)

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