Translations of graphs

Introduction to Translations of Graphs

  • Translations of graphs involve shifting the graph of a function to a different location in the Cartesian plane without changing its shape or orientation.
  • A translation can occur along the x-axis, the y-axis, or both simultaneously.
  • In mathematical notation, a translation can be described as (x, y) → (x + a, y + b). This indicates all points (x, y) on the original graph are moved ‘a’ units horizontally and ‘b’ units vertically to reach their new position in the translated graph.

Horizontal Translations

  • A horizontal translation moves the graph to the left or the right along the x-axis.
  • A translation of (x, y) → (x + a, y) involves moving the graph a units to the left if ‘a’ is negative, or a units to the right if ‘a’ is positive.

Vertical Translations

  • A vertical translation involves moving the graph up or down along the y-axis.
  • A translation of (x, y) → (x, y + b) means the graph moves b units down if ‘b’ is negative, or b units up if ‘b’ is positive.

Combining Translations

  • A graph can be translated both horizontally and vertically at the same time.
  • This is denoted as (x, y) → (x + a, y + b), meaning the graph is moved a units horizontally (left for negative ‘a’, right for positive ‘a’) and b units vertically (down for negative ‘b’, up for positive ‘b’).

Examples of Translations

  • For instance, consider the function f(x) = x². A translation (x, y) → (x + 2, y - 3) would result in the new function f(x) = (x - 2)² - 3.
  • The function f(x) = x³ when translated through (x, y) → (x - 1, y + 2) would result in the new function f(x) = (x + 1)³ + 2.

Conclusion

  • Understanding how to perform and interpret graph translations is vital in algebra. It allows the exploration of how alterations to function rules can affect the graph of the function.
  • Clear comprehension of the effects of positive and negative translations on the coordinates of a graph enables the prediction of how function graphs will behave under these transformations.
  • Regular practice with different function graphs and translations helps reinforce learnt concepts and aids in efficient problem-solving.