Exam Revision Flashcards
Revise for exams
N = ?
the set of positive integers and zero
Z = ?
the set of all integers
Z+ = ?
the set of positive integers without zero
Q = ?
the set of all rational numbers
Q+ = ?
the set of positive rational numbers without zero
R = ?
every number
R+ = ?
any number greater than zero
Irrational = ?
infinite numbers
How to solve simultaneous equations
SSLE or graphing intersection
Solution of quadratic equations ?
If x^2 = k, then = +/- SqRt (k)
= x-axis
= solutions of polynomials
Does x,y satisfy the equation? how does this work
substitue x and y into the equation and then compare answer to equation on the graph –> is there a point with those values
how to find y-intercept
let x = 0
how to find x-intercept
let y = 0
Finding the quadratic equation from a graph
Factorised form = x-intercept + point –> y = (x-a)(x-b)
Expanded form = any 3 points –> y = ax^2 + bx + c
–> substitute x-intercept values for a + b
–> add lettered variable “k” after y
–> solve for “k”
–> rearrange equation to y = k(x-a)(x-b)
Finding the quadratic equation in expanded form
3 points enter coordinates in SPREADSHEET label columns menu-->Stats-->stat calcs--> option 6 Sub in
finding the equation of a line
the gradient + point on the line
two points on the line
R- = ?
all numbers less than zero
Z- = ?
negative integers without zero
representing number of elements in a set
n(A) = 6
what is a subset
If p and q are two set and all of the elements of p are in q then
–> (2,4,6)
Intersection
elements that are COMMON in both sets
Union
all elements in both sets
Disjointed sets
neither sets have elements in common
How do you writie set notation
- X < 3 = (-infinity, 3]