JCHL Functions - Exam Solutions

Описание: A crash course in identifying Functions, and a walk-through of some questions that appeared on the Junior Certificate Higher Level Mathematics Paper 1 involving Functions. This is a follow on from my video "JCHL Patterns and the Nth Term - Exam Solution" which you can access here:

   • JCHL Patterns and the Nth Term - Exam Solu...  

Also featured in this video was the "Geogebra" graphing website, available at:

https://www.geogebra.org/m/qujNcJjQ

To get the most out of this video, pause before each solution starts, and attempt the question yourself.

Exam Questions covered:
2017 Q15
2018 Q8(b)

Key Points
A function is a relationship between a set of inputs and outputs, so that every input has ONLY ONE output.

Input, Domain, “x”, all refer to the same thing.

Output, Codomain/ Range, y, f(x), all refer to the same thing.

Linear Functions:
Highest power of x is 1.
f(x) = ax + c
If “a” is positive, graph will go up
If “a” is negative, graph will go down
“c” is where the graph crosses the y axis

Quadratic Functions:
Highest power of x is 2.
f(x) = ax² + bx + c
“c” is where the graph crosses the y axis
If “a” is positive, graph will have a “u” shape 😊
If “a” is negative, graph will have an “n” shape ☹
The roots of your graph will be where it crosses the x axis.

My next video will be on Graphing Functions and will be a follow on from this one. Stay tuned.

Mr. Ludden