Rational Expressions Flashcards

Grade 10 · Math · Flashcards

Master the vocabulary and procedures for working with rational (algebraic fraction) expressions.

Flashcards

Rational expression
A fraction whose numerator and denominator are both polynomials
Domain restriction
Any x-value that makes the denominator equal zero; must be excluded
Simplifying rational expressions
Factor completely, then cancel identical factors in numerator and denominator
Multiplying rational expressions
Multiply numerators together and denominators together, then simplify
Dividing rational expressions
Multiply the first expression by the reciprocal of the second, then simplify
Adding rational expressions (same denominator)
Add the numerators; keep the denominator the same
Adding rational expressions (different denominators)
Find the LCD, rewrite each fraction, then add numerators
Least Common Denominator (LCD)
The smallest polynomial divisible by all denominators in the problem
Reciprocal of a rational expression
Swap numerator and denominator; used in division
Can you cancel terms in rational expressions?
No — you can only cancel common factors, not individual terms being added
Why can't the denominator equal zero?
Division by zero is undefined in mathematics
Complex rational expression
A rational expression with fractions in the numerator or denominator; simplify by multiplying by the LCD
Extraneous solution
A solution found algebraically that must be rejected because it creates a zero denominator

Get a personalized course on Rational Expressions built around your child.