Maths Flashcards
Nano-
10^-9
Micro-
10^-6
Milli-
10^-3
Centi-
10^-2
Deci-
10^-1
Kilo-
10^3
Mega-
10^6
Giga-
10^9
Pressure
Force / area
Finding a highest common factor
Multiply factors in both lists
Finding a lowest common multiple
Multiply all factors, disregarding multiples
Systematic listing strategies
If there are m ways of doing one task, and for each of these tasks there are n ways of doing another task, then the total number of ways the two tasks can be done is m x n ways
Recurring decimals into fractions
Let x = blah
100x = 100 blah
And so on
Upper and lower bounds
We can do this
Percentage
Number of parts per hundred
Expressing one quantity as a percentage of another
Number / total x100
Express a quantity as a fraction of another…
…pips
Original value
Let X = original
X x (1-discount in decimal) = new value
Direct proportion
x α y
Inverse proportion
x α 1/y
What is the difference between an equation and an identity
Equation - states that two expressions are equal. You find the values for which the expression are equal (equations are not always true)
Identity - an equation which is always true, no matter what values are substituted (can be written with triple equals)
Nth term
Un = a(n+1)d
Subtended angles
An angle between an arc
Angle rules
Corresponding (F) - equal
Alternate (Z) - equal
Supplementary (C) - add to 180
Sum of interior angles
N - 2 x 180
Sum of exterior angles
360
Congruence criteria for triangles
SSA, SSA, ASA, RHS
Circle theorems
- Angle at the centre is twice that of the angle at the circumference
- Angle in a semicircle is 90
- Angles in the same segment are equal
- Angel between a radius and a tangent is 90
- Cyclic quadrilaterals add to 180
- Alternate segment theorem
Alternate segments theorem
Angle between a chord and a tangent is equal to the one in the alternate segment
Area of a parallelogram
Base x vertical height
Volume of a cylinder
πr^2h
Sin(30)
1/2
Sin(45)
1/root 2
Sin(60)
Root 3 /2
Cos(30)
Root 3 /2
Cos(45)
1/ root 2
Cos(60)
1/2
Frequency density
Frequency / class width
Estimating range of grouped data…
As u would expect
Estimating mode of grouped data
Modal class
Estimating mean of grouped data
Sum of the (frequency x midpoint) divided by the frequency
Bivariate data
…
Mutually exclusive
…
Independence
…
Total surface area of a cylinder
2πrh + 2πr2
Relationships between proportion s
1) figure out the element you want to eliminate
2) multiply proportions to that it has the same index
3) eliminate and ignore constants
Total surface area of a cuboid
2lw x 2lh x 2wh
Triangles inside other shapes
Are they isocèles?
Circle theorems
Using algebra might help
Quadratic nth terms
Compare the quadratic sequence to the given sequence, in that order
Tan(30)
Root 3 over 3
Tan(60)
Root 3
Tan 45
1
DOTS for negative quadratics
(-x + a)(x + a)
If dividing powers from powers
You might be substracting à Negatice
Write long-hand to avoid errors
If given 3 equations
1) variable that is the same in 2 and 3- get it in terms of variable 3 in the 2nd equation
2) sub this into first equation - gives first variable in terms of 3rd variable
3) sub everything into original equation
Changing signs
If you change all of the signs in a bracket, do not change the one in the outside too
Area of a parallelogram
Base x vertical height
Clocks
Observe whether you are counting the distance the hand has already travelled, or the distance it is yet to travel
Draw a diagram to help
