Quadratic functions and graphsAQA A-Level Maths: Flashcards

What these 13 flashcards ask

What is the general form of a quadratic function?
What shape is the graph of y=ax^2+bx+c if a<0?
State the line of symmetry of y=ax^2+bx+c.
What form does completing the square give?
Complete the square for x^2+bx.
Complete the square: x^2-6x+13.
Complete the square: 2x^2+8x-3.
What is the discriminant of ax^2+bx+c?
What does b^2-4ac0 tell you?
What does b^2-4ac=0 tell you?
What does b^2-4ac<0 tell you?
Condition on k for x^2-kx+(k+3)=0 to have a repeated root?
A parabola has a0 and b^2-4ac<0. Where is it?

Exam questions on Quadratic functions and graphs

The quadratic function $f$ is defined by $f(x)=x^{2}-6x+13$ .
Show that the equation $f(x)=0$ has no real roots.2 marks
The quadratic function $g$ is defined by $g(x)=2x^{2}+8x-3$ .
Solve $g(x)=0$ , giving your answers in exact form.2 marks
The equation $x^{2}-kx+(k+3)=0$ , where $k$ is a constant.
Find the values of $k$ for which the equation has a repeated root.3 marks

Written by the Exaim team, led by Shaun Daswani (Head of Upper Secondary, Improve ME Institute; MSc Financial Mathematics, Imperial College London; BSc, UCL) and Jason Daswani (operational lead, Improve ME Institute; LSE).