General Mathematics · 2nd secondary · First Term

Limits — Finding the limit of a function algebraically

About this lesson

This unit teaches students how to find the limit of a function algebraically, without relying on tables or graphs. It covers limits of polynomial functions through direct substitution, and introduces theories for combining limits (such as sums, products, quotients, and powers). The unit also explains how to handle cases where direct substitution gives an undefined expression, using techniques like factorization and using conjugates to simplify the function before taking the limit. Examples include limits involving rational functions, square roots, and expressions that simplify to a constant. By the end, students should be able to compute limits of polynomial functions, apply limit laws, and use algebraic manipulation (factorization, conjugation) to evaluate limits that initially appear indeterminate.

Main topics in this lesson

  • Limit of a polynomial function
  • Theories of limits (sum, product, quotient, constant multiple, power)
  • Direct substitution
  • Using factorization to simplify functions
  • Using conjugates to simplify functions
  • Corollaries on limit theories (e.g., limits of expressions like (x^n - a^n)/(x - a))

Key terms and vocabulary

  • Limit of a function
  • Polynomial function
  • Direct substitution
  • Synthetic division
  • Conjugate
  • Long division
  • Theory of limits

Questions and answers on Limits — Finding the limit of a function algebraically - practice and revision

Multiple choice questions on this lesson in General Mathematics for 2nd secondary, First Term, with practice exercises for revision and exam preparation.

1

إذا كانت نها(س→2) د(س) = 3، فما قيمة نها(س→2) [د(س)]²؟

  • 1 3
  • 2 6
  • 3 9
  • 4 12
2

إذا كانت نها(س→3) د(س) = 2، فما قيمة نها(س→3) [4 × د(س)]؟

  • 1 2
  • 2 4
  • 3 6
  • 4 8
3

ما قيمة نها(س→2) (3س² + 2س − 1)؟

  • 1 15
  • 2 12
  • 3 18
  • 4 10
4

ما قيمة نها(س→1) (س³ − 1) ÷ (س − 1)؟

  • 1 1
  • 2 3
  • 3 0
  • 4 9
5

ما قيمة نها(س→2) (س³ − 8) ÷ (س − 2)؟

  • 1 4
  • 2 8
  • 3 12
  • 4 16
6

ما قيمة نها(س→0) (√(س + 9) − 3) ÷ س؟

  • 1 1/6
  • 2 1/3
  • 3 3
  • 4 6

Turn this unit into a ready quiz

Generate a quiz from this unit, send it to your class, and let the answers be graded for you.

Start free