120 likes | 276 Views
GCSE Revision 101. Maths Transforming Graphs. © Daniel Holloway. The Basics. Transforming graphs is not too dissimilar from transforming shapes. Whereas you can translate, rotate, reflect and enlarge shapes; you can translate , stretch and reflect graphs.
E N D
GCSE Revision 101 Maths Transforming Graphs © Daniel Holloway
The Basics Transforming graphs is not too dissimilar from transforming shapes. Whereas you can translate, rotate, reflect and enlarge shapes; you can translate, stretch and reflect graphs. We use the notation f(x) to denote a function of x. A function of x is any algebraic expression where x is the only variable.
The Basics There are six rules you need to learn about transforming graphs. To show these rules, we will use the following graph. This is the graph y = f(x)
Translating Graphs Rule 1: This is a translation of the graph in the vector ( ) in the y-direction 0 a y = f(x) + a
Translating Graphs Rule 2:This is a translation of the graph in the vector ( ) in the x-direction a 0 y = f(x – a)
Stretching Graphs Rule 3:This is a stretch of the graph by a scale factor of k in the y-direction Note thatthey crossat the x axis y = kf(x)
Stretching Graphs Rule 4:This is a stretch of the graph by a scale factor of 1/t in the x-direction Note thatthey crossat the yaxis y = f(tx)
Reflecting Graphs Rule 5:This is a reflection of the graph in the x-axis y = -f(x)
Reflecting Graphs Rule 6:This is a reflection of the graph in the y-axis y = f(-x)
Examples of Transformations y y 5 5 0 0 x -5 5 x -5 5 The grid shows the graph of y=x2 for -2 ≤ x ≤ 2 The dotted line shows the same graph. Describe the transformation taking it to the new line on the grid. y = (x + 3) 2
Examples of Transformations y y 5 5 0 0 x -5 5 x -5 5 The grid shows the graph of y=x2 for -2 ≤ x ≤ 2 The dotted line shows the same graph. Describe the transformation taking it to the new line on the grid. y = x2 - 2
Examples of Transformations y y 5 5 0 0 x -5 5 x -5 5 The grid shows the graph of y=x2 for -2 ≤ x ≤ 2 The dotted line shows the same graph. Describe the transformation taking it to the new line on the grid. y = 2x2