Maths - Half Yearly Flashcards
if Sin € = AB/AC
Find AB
Find AC
AB=AC*Sin €
AC=AB/Sin €
angles of elevation/ depression.
angle of elevation: when looking up the angle between line of sight and horizontal
angle of depression: when looking down angle between line of sight and horizontal. alt. angle to angle of elevation
Explain Three figure bearings.
aka true bearings, written as 000-360 degrees. measures degrees clockwise from north.
Explain compass bearings.
written as a measurement between 0 and 90 degrees east or west from north or south. eg N80E
the two triangles needed to find exact ratios of 30, 60 and 45.
draw an equilateral triangle with all sides 2. split down the middle. the triangle now has sides 1, 2 and (root)3 and angles 90, 60 and 30.
draw an isosceles, right angle triangle with two sides 1 and hypotenuse (root)2.
the three types of clusters and what they look like.
symmetrical: .-/-.
positively skewed: ./|:~.
negatively skewed: .~:/|.
2 properties of trapeziums:
one pair of parallel sides
no symmetry
4 properties of a kite:
2 pairs of adj. sides equal
one pair of opp. angles equal
1 axis of symmetry
diagonals intersect at right angles
4 properties of a parallelogram:
opp. sides equal and parallel
opp. angles equal
no symmetry
diagonals bisect each other
6 properties of a rhombus:
all sides are equal opp sides are parallel opp. angles are equal 2 axis of symmetry diagonals bisect at right angles diagonals bisect angles of rhombus
how do you test for parallel lines
prove alt. angles, corresp. angles or co-int. angles
what is the proof for the angle sum of a triangle?
draw a triangle and draw a line parallel to one of the sides on one of the corners and then use alternate angles and shit
/__ < that’s a really bad exterior angle. what’s the proof?
just know it ceebs drawing it
angles sum of a polygon?
A=(n-2)*180
what is an outcome?
a result
what is a sample space and how do you write one?
all possible outcomes: {1,2,3,4,5,6}
what is an event?
a possible outcome.
p(event)=number of outcome matching event / total number of outcomes.
complimentary event?
the complimentary of an event is the rest of the outcomes in the sample space. the compliment of E is written as
_
E
what is a mutually exclusive event:
when if one event occurs the other cannot eg odd and even numbers
non mutually exclusive events?
e.g prime and odd numbers, in a venn diagram there would be an overlap
relative frequency is?
the number of times an event occurred compared to the total frequency of outcomes.
independent and dependent events?
when the outcome of one event depends on the other it is dependent
eg without replacement
what are the 3 ways to work out 2 stage events?
list, table and tree diagram
when do you change the direction of the sign in linear inequations?
when multiplying or dividing by a negative or reversing the sides.
what are the three ways of solving quadratics?
factorizing, completing the square and the quadratic formula.
what are the steps to completing the square?
- move the constant to the RHS
- divide by the coefficient of x^2
- half the coefficient of x, square it and add it to both sides
- write LHS as a perfect square
5 square root all tha shit
what is the quadratic formula?
x=(-b+-|b^2-4ac|)/2a
|= square root
what are the 3 ways of solving simultaneous equations with a brief description
graphically: draw it on a graph and write the coordinates where the two lines meet.
substitution: sub in the value of one pro-numeral into the equation
elimination: add or subtract the two equations.
