Year 12 Maths Flashcards
(27 cards)
What is self-selection sampling?
Sampling choice where the person answering has the option to participate or not.
What is cluster sampling
The population is divided into groups called “clusters”. These clusters are then randomly selected to form a sample.
What is opportunity sampling?
Sampling when it is convenient for you, and has no quota.
What is quota sampling?
The individual “finds” people until the said amount is complete.
What is stratified sampling?
Proportional representation of each group is chosen.
For example, out of a group of 150 people, 45 had a cheese sandwich and you wanted to find a sample of 20, you would do 45/150 times by 20.
What is systematic sampling?
The people put in an order (e.g alphabetical) and you pick every nth person.
What is simple random sampling?
Assign candidates a number, and randomly generate a number (using a calculator), until you have a sample size.
What is a census?
Where everyone in a population is asked
What are the two trig identities for year 12?
sin^2 +cos^2=1
tan=sin/cos
What is the integration and differentiation in variable acceleration order?
Position>Velocity>Acceleration are differentiated.
Acceleration>Velocity>Position are integrated.
What do you do when completing the square to get a turning point?
The number inside the brackets change, but the one outside the brackets does not.
What is the formula for the area of a sector?
Theta/360 times by pi times the radius squared.
If the products of 2 gradients are -1…
…then the 2 lines are perpendicular.
How to find the negative reciprocal?
Change the sign and make it 1/n.
When an intersection is mentioned…
…use simultaneous equations.
Equation of circle with a centre of (0,0) is…
…x^2 +y^2=r^2
What is the completed square form of a circle?
(x-a)^2+(y-b)^2=r^2
Independent vs mutually exclusive?
Independent=One variable occurring does not have an affect on the other occurring.
Mutually exclusive=Two variables cannot happen at the same time.
What is the outlier formula?
Mean plus 2 times the standard deviation.
Mean minus 2 times the standard deviation.
How to find the expected and the most likely number in a binomial distribution?
Expected number: Times the numbers inside the bracket.
Most likely number=The integer closest to the expected number.
In a velocity time graph, the gradient is…
the accleration.
In a displacement time graph, the gradient is…
the velocity.
How to know if an equation has equal roots?
The discriminant is equal to 0
How to know if an equation has unequal roots?
The discriminant is not equal to 0.
