MATH Flashcards
1 tonne
1000 kg
1 litre
1000 cm cube
1 m cube
1000 litres
1 gram
1000 mgm
1 year
52 weeks, 365.25 days
simple interest
PRT/100
compound interest
p(1+ r/100) t
area of trapezium
( a + b / 2 )* h
circle
area pirsquare perimeter 2pir
semicircle
area * .5 perimeter : pi r + 2r
sector area
pi r square x angle/360
length of an arc
2pi r x angle/360 for perimeter just add 2r to that value.
surface area of cylinder
2πrh+2πr2
volume of a cylinder
pi r square x h
area of parallelogram
bxh or ab x sin
(a-b) square
a square - 2ab + b square
a square + b square
(a+b) square - 2ab
a square - b square
(a+b)(a-b)
exponential increase
a(1+r) t
exterior angles of polygon
add up to 360.
sum of interior angles of a polygon
(n-2) x 180
cosine rule (length of a side)
a2= b2+c2 -2bc cos A
cosine rule angle
cos A = b2+c2- a2 /2bc
when tan value is negative
subtract from 360 and 180
quadratic sequences
multiply the second common ratio by 1/2 and then use simultaneous equations to find b and c. e.g is Ansquare+ bn + c
OR
for finding B
look at the first commin ratio and use the formula
3A + B = common ration
and for c use
a + b + c = first number
MARA JUST MAKE TABLE AND FIND VERTICAL PATTERN
geometric sequence formula
this is for when the common ratio is being multipled instead of simple additition. the common ratio becomes the base of an exponent. and to find the power its n, and examine the pattern to see whether something needs to be added or subtracted from it.
if sin value is negative..
add 180 and subtract 360
positive tan value
original and add 180
positive cos value
original value and subtract from 360
simultaneous equation tip
- when you get a fractoion multiply the denominator by product and other vaiable only.
when a question mentions “at the same time” after mentioning two different speeds on a race what methodology would we apply?
LCM
when a line crosses the x axis, which value do we take as zero?
y value
and vice versa
completing the square method
a equals x and it’s coefficient
b must be divided by two
c is outside of the square expression and is b square is subtracted from c
how do we find stationary points of a graph
dx/dy = 0
first, differentiate and then make the equation equal zero and find two possinle values for x by factorization.
then input those two x values into the original equation without diff. to get y.
how to tell of a stationary point is a local maximum or minimum?
take a second derivative.
input values of x you previously found when gradient was zero.
if its a negative result ; local maximum
and if its positive ; minimum
how to find original price from given sale price?
subtract discount with 100 = x
divide sale price by x percent
how to find value of r in compound interest with my calculator
- divide by P
- take square root
- subtract and then multiply by 100
which angle do we use when finding area of a non right triangle
the included angle
the angle which is made up of the two given lengths
to find absolute value |x|
and the squares, x and y
and then take square root
what are triangle numbers
sequence :
1/2n(n+1)
1,3,6,10
how to find each interior angle
180(n-2) / n
kinematics in trains
add length of train with distance of railway ti get total distance.
how do we deal with time in upper bounds
we minimize it so subtract it!
graphs. how do we find the point of intersection
input y of equation 1 into second equation. solve use simultaneous equations
graphs. area enclosed
plot all the coordinates u found on a graph.
area of non right traingle
1/2bhsinangle
how do we implement the elimination method?
make sure terms you cancel are equal. ( u can multiply, only on one equation and choose either x or y. make sure they are polar. u can add minus as a common.
