The composite function gf($$x$$) is the combination of f($$x$$) and g($$x$$). The output from f($$x$$) is the input for g($$x$$).

Writing composite functions

Maths

Checking and securing understanding of functions

Defining function notation

Finding the inverse of a function

Solving equations involving functions

Solving equations involving composite functions

General algebraic forms for specific number properties

Making conjectures about patterns and relationships

Proving or disproving a statement

Writing a generalised statement about specific number properties

Writing a proof

Logical arguments

Multiple approaches to logical arguments

Problem solving with functions and proof

In this future unit, pupils continue to explore composite functions, thereby building on their work from this unit. Pupils need to understand function notation from this unit as this is used in iteration.

The functions unit requires pupils to write composite functions and pupils will need to draw on their understanding of how to manipulate various algebraic expressions and equations, including algebraic fractions.

In this unit pupils will further develop their understanding of algebraic notation and graphs by learning about functions, their inverses and composite functions.

Functions and proof

__________ function is where another function is applied to the output of a function.

The output of $${\text{g}}(8)$$ being input in to $${\text{f}}(x)$$

The output of $${\text{f}}(8)$$ being input in to $${\text{g}}(x)$$

The output of $${\text{g}}(8)$$ being input in to $${\text{h}}(x)$$

The output of $${\text{h}}(8)$$ being input in to $${\text{g}}(x)$$

The output of $${\text{f}}(8)$$ being input in to $${\text{f}}(x)$$

Match the notation to the correct language.

If $${\text{f}}(x)=2x$$ and $${\text{g}}(x)=5x-1$$ then $${\text{fg}}(5)=$${{}}.

If $${\text{f}}(x)=2x$$ and $${\text{g}}(x)=5x-1$$ then $${\text{gf}}(5)=$${{}}.

If $${\text{f}}(x)=9x$$ and $${\text{g}}(x)=3-2x$$ how do we express the function $${\text{fg}}(x)$$?

If $${\text{f}}(x)=x^2$$ and $${\text{g}}(x)=3-2x$$, how do we express the function $${\text{fg}}(x)$$?

For the function $$\text{f}(x)$$ if $$\text{f}(10)=35$$ then $$10$$ is a value in the...

If $$\text{f}(x)=5x$$, $$\text{g}(x)=3x+4$$ and $$\text{h}(x)=1-2x$$ evaluate and order the below from greatest to smallest value.

Writing composite functions

Lesson outcome