Functions and Formulae Flashcards
1
Q
What is the method for changing the subject of a formula, such as y = 3x + 5?
A
Write down what has been done to x in order to get y
Undo this in reverse order
Write equal to x
2
Q
What do you need to remember when expanding double brackets?
A
Use the grid method or ‘eyebrows and smiley face’
3
Q
What is an expression?
A
A collection of algebraic terms separated by + or - such as 3x+5
4
Q
What is an identity?
A
An equation which works for every value of letter such as 5(x+7) = 5x+35
5
Q
If f(x) = 3x +7, what is f(1)?
A
f(1) = 3 x 1 + 7 = 10
6
Q
If g(x) = x^2 - 6x, what is g(2)?
A
g(2) = 2^2 - 6x2 = -8
7
Q
Expand these brackets (x+5)(x+9)
A
x^2 + 14x + 45
8
Q
Expand these brackets (x+5)(x-9)
A
x^2 - 4x - 45
9
Q
Expand these brackets (x-5)(x-9)
A
x^2 - 14x + 45
10
Q
Expand these brackets (x-5)(x+9)
A
x^2 + 4x - 45
