Mathematics

Problem

x

approaches

5

, the expression

\dfrac{x^2-25}{x-5}

takes the form

\dfrac{0}{0}

. (a) State the name of this form. (b) Explain in one sentence why this form prevents evaluation of

\displaystyle \lim_{x\to5}\dfrac{x^2-25}{x-5}

by direct substitution.