Maths - Transformations

2021-01-06
2 min read
What is the transformation as a vector for $y = f(x) + a$??

$$ \left(\begin{matrix} 0 \\ a \end{matrix}\right) $$

What does the transformation $y = f(x) + a$ mean in simple terms??

Move the graph up by $a$.

What is the transformation as a vector for $y = f(x + a)$??

$$ \left(\begin{matrix} -a \\ 0 \end{matrix}\right) $$

What does the transformation $y = f(x + a)$ mean in simple terms??

Move the graph back horizontally by $a$.

What is the transformation to $f(x)$ to make the graph forwards by $a$??

$$ f(x - a) $$

What is the transformation to $f(x)$ to move the graph down by $c$??

$$ f(x) - c $$

What is the equation of line for the asymptote of $\frac{1}{x}$ at $y = 0$ when you transform it by doing $\frac{1}{x} + 1$??

$$ y = 1 $$

What does the transformation $y = af(x)$ mean??

A vertical stretch by scale factor $a$.

What does the transformation $y = f(ax)$ meant??

A horizontal stretch by scale factor $\frac{1}{a}$.

If a quadratic has roots $(3, 0)$ and $(-3, 0)$ and undergoes the transformation $y = f(2x)$, what are the new roots??

$(1.5,0)$ and $(-1.5,0)$

What’s another way of saying a horizontal stretch by scale factor $\frac{1}{2}$??

The $x$-coordinates halve.

What is the transformation for $y = -f(x)$??

A reflection in the $x$-axis.

What is the transformation for $y = f(-x)$??

A reflection in the $y$-axis.

What do transformations “outside” the function represent??

Vertical transformations.

What do transformations “inside” the function represent??

Horizontal transformations.

2021-01-07

What happens to the co-ordinates for $f(2x)$??

They all halve.

If the original point for $f(x)$ is $(4, 14)$, what is the new co-ordinate for $f(2x)$??

$$ (2, 14) $$

Which points stay in place for a transformation like $f(ax)$??

The points on the $y$-axis.

Which points stay in place for a transformation like $af(x)$??

The roots, i.e. the points on the $x$-axis.

When given a transformation question where you’re asked to sketch a graph, what should you do first??

Describe the transformation in plain English.

What happens to the co-ordinate $(2,4)$ for $2f(x)$??

$$ (2, 8) $$

What happens to the co-ordinate $(3,6)$ for $f\left(\frac{1}{2}x\right)$??

$$ (6, 6) $$


Metadata
date: 2021-01-06 10:44
tags:
- '@?maths'
- '@?school'
- '@?year-1'
- '@?public'
title: Maths - Transformations