Algebra 3/4

Algebra 3/4 delves into advanced algebraic concepts, including polynomial functions, rational expressions, and complex numbers.

Basic Concepts

Rational Expressions

Understanding Rational Expressions

A rational expression is a fraction where the numerator and denominator are both polynomials. They're like regular fractions, but with algebraic expressions!

Simplifying Rational Expressions

To simplify, factor both the numerator and denominator and cancel out any common factors. Always check for restrictions: values that make the denominator zero are not allowed.

Operations with Rational Expressions

  • Addition/Subtraction: Get a common denominator, just like with regular fractions.
  • Multiplication/Division: Multiply numerators and denominators straight across; for division, multiply by the reciprocal.

When Do We Use Rational Expressions?

Rational expressions appear in science, engineering, and even finance when dealing with rates, ratios, and proportions.

Examples

  • \( \frac{x^2 - 9}{x + 3} \) simplifies to \( x - 3 \) for \( x eq -3 \).

  • Adding \( \frac{1}{x} + \frac{2}{x^2} \) gives \( \frac{x + 2}{x^2} \).

In a Nutshell

Rational expressions are fractions made up of polynomials.