Graphs 8
2 marks · EasyThe graph of is stretched parallel to the y-axis by a scale factor of 3.
Write down the equation of the new graph.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
Show answer
y = 3f(x)
Also accept: y = 3·f(x); y = f(x) multiplied by 3
Common mistakes: Writes y = f(3x)
Show mark scheme and worked solution
Marking points
M1 · 1 mark · M1: Identifies that a stretch in the y-axis multiplies function by 3.
A1 · 1 mark · A1: Writes correct equation y = 3f(x).
Worked solution
A stretch in the y-direction multiplies the function output by the factor. So, y = 3f(x).