- #1
powp
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How do I prove the following:
lim x^2 + x - 12 = 7
x-> 3 ------------
x-3
here is my solution so far but think it is wrong
Given E > 0 and D > 0 such that
|x^2 + x - 12 |
|------------ - 7| < E whenever 0 < |x-3| < D
| x-3 |
|(x-3)(x+4) |
|------------ - 7| < E whenever 0 < |x-3| < D
| x-3 |
|x + 4 - 7| < E
|x - 3| < E
Not sure where to go from here or if I am even close.
Thanks
Peter
PS I am new to proofs
lim x^2 + x - 12 = 7
x-> 3 ------------
x-3
here is my solution so far but think it is wrong
Given E > 0 and D > 0 such that
|x^2 + x - 12 |
|------------ - 7| < E whenever 0 < |x-3| < D
| x-3 |
|(x-3)(x+4) |
|------------ - 7| < E whenever 0 < |x-3| < D
| x-3 |
|x + 4 - 7| < E
|x - 3| < E
Not sure where to go from here or if I am even close.
Thanks
Peter
PS I am new to proofs