Pure year 2 Flashcards
(94 cards)
Start by assuming its not true
Use steps to lead to something impossible
In proofs
how can rational and irrational numbers be differentiated?
What is Q?
The set of all rational numbers
What does the modulus of a number do?
Make it not negative
When f(x) >= 0
the modulus of f(x) =
When f(x) < 0
the modulus of f(x) =
How to sketch y = modulus(ax+b) ?
Sketch y = ax+b
What is domain and range?
Domain = all possible inputs
A mapping is a function if every input has a distinct output
functions can be what or what?
What type of function is fg(x)?
Composite
What is the inverse of f(x)?
f⁻¹(x)
What does y=f(x) look like in relation to y=f⁻¹(x)?
A reflection in the line y=x
How do the domains and ranges of inverse functions relate?
The domain of f(x) is the range of f⁻¹(x)
How to sketch y = modulus(f(x))?
Sketch f(x)
How to sketch y = f(modulus(x))?
Sketch f(x) for x>=0
What does f(x+a) do?
Translation left by a
What does f(x) + a do?
Translation up by a
What does f(-x) do?
Reflect in the y-axis
What does -f(x) do?
Reflect in the x-axis
What does f(ax) do?
Horizontal stretch of scale factor 1/a
What does af(x) do?
Vertical stretch of scale factor a
Formula for nth term of an arithmetic sequence
Un = a + (n-1)d
Formula for the sum of the first n terms of an arithmetic sequence
Sn = (n/2)(2a + (n-1)d)
Formula for the nth term of a geometric sequence
Un = ar^(n-1)