Sketching graphs

Sketching

• A sketch of a graph shows all the major features
• These usually include turning points and places where the graph crosses the axes

Factors and roots

• If a function is factorised you can work out the points where its graph crosses the x-axis
• These are called the roots of the function
• You can find them by working out the x-values that make each factor equal to zero

Graph sketching checklist

• Your sketch should be clear and neat
• Use a ruler for any straight lines
• Label your axes and the origin
• Label your graph with its equation
• Label any turning points if you are asked to find them
• Label any points where the graph crosses the axes

Sketching cubs-two to watch

• If one factor is x then the curve will pass through the origin
• If one factor is squared then the curve will just touch the x-axis at the corresponding point