Direct Substitution

Definition

Direct substitution is an algebraic method used to evaluate limits by plugging in the desired value directly into the expression. It works when there are no undefined values or indeterminate forms involved.

Analogy

Think of direct substitution like ordering your favorite pizza from your favorite pizzeria. You know exactly what toppings and crust you want, so you can directly substitute those choices into your order without any complications.

Related terms

Indeterminate Forms: Expressions that cannot be evaluated using direct substitution because they result in ambiguous or undefined values.

L'Hôpital's Rule: A technique used for evaluating limits involving indeterminate forms by taking derivatives of both numerator and denominator until an evaluatable form is obtained.

Rational Functions: Functions defined as ratios (quotients) of two polynomials, often encountered when dealing with direct substitution.