Question

How do you find the limit of `x / (x^2 + 49)` as x approaches `7^-`?

Answer 1

By substitution.

Explanation:

As `xrarr7` the numerator approaches `7` and the denominator approaches `(7^2)+49 = 98`.

`lim_(xrarr7^-)x/(x^2+49) = 7/(7^2+49) = 7/98 = 1/14`