GCSE · Graphs of functions

Transformations of graphs (y = f(x) + a, y = f(x + a), y = −f(x), y = f(−x))Exam-style questions

Move a graph without plotting it again. A number added outside the f moves the curve up or down; a number added inside the bracket moves it sideways, the opposite way to its sign; a minus sign outside reflects it in the x-axis and a minus sign inside reflects it in the y-axis. Track the key points, describe each change fully, combine two changes, write the new equation, and use the same four rules on the sine and cosine waves.

20 questions · GCSE (Higher) level · mark scheme and worked solution on each · no sign-up to try

DifficultyAllLevel 2Level 3Level 4Level 5
  1. 1
    f(x)=x2−8x+12\mathrm{f}(x) = x^2 - 8x + 12

    The graph of y=f(x−a)+by = \mathrm{f}(x - a) + b has its turning point at (1,3)(1, 3)

    Find the value of aa and the value of bb.

    You must show all your working.

    (4 marks)
    Level 5 · 4 marksTry it
  2. 2
    The curve CC has equation y=x2−10x+22y = x^2 - 10x + 22
    (a) Show that x2−10x+22x^2 - 10x + 22 can be written as (x−5)2−3(x - 5)^2 - 3

    (2 marks)
    (b) Write down the coordinates of the turning point of CC.

    (1 mark)
    (c) CC is reflected in the yy-axis to give the curve DD.

    Find the equation of DD in the form y=x2+px+qy = x^2 + px + q

    (2 marks)
    (d) Find the exact xx-coordinates of the points where DD crosses the xx-axis.

    You must show your working.

    (2 marks)
    Level 5 · 7 marksTry it
  3. 3
    The graph of y=sin⁡xy = \sin x is translated by the vector (ab)\begin{pmatrix} a \\ b \end{pmatrix}, where 0<a<1800 < a < 180

    The translated graph has a minimum point at (300°,−4)(300°, -4)

    Find the coordinates of the point where the translated graph crosses the yy-axis.

    You must show all your working.

    (5 marks)
    Level 5 · 5 marksTry it