PrerequisitesPrerequisite

Substituting an expression into a function

Replace each by the entire new input expression.

  • Put the new input in parentheses.
  • Expand and simplify only after every has been replaced.

Example 1

Replace by

Evaluate the function at the stated input.

Write the square as two identical factors.Now multiply into any remaining parentheses.

Example 2

Find and simplify .

Write the square as two identical factors.Now multiply into any remaining parentheses.

Your turn

5 practice questions
Question 1

Find and simplify .

Check answer
Question 2

Find and simplify .

Check answer
Write the square as two identical factors.Now multiply into any remaining parentheses.
Question 3

Find and simplify .

Check answer
Write the square as two identical factors.Now multiply into any remaining parentheses.
Question 4

Find and simplify .

Check answer
Write the square as two identical factors.Now multiply into any remaining parentheses.
Question 5

Find and simplify .

Check answer
Write the square as two identical factors.Now multiply into any remaining parentheses.