C2 Flashcards
Dividing polynomials by (x±p)
Put in order of powers
1) divide highest power of x by x
2) put the answer in the column that’s up and along to the right
3) multiplly by (x±p) then subtract
4) bring the next term down
Repeat for all terms
Factor theorem
If f(x) is a polynomial and f(p)=0
Then (x-p) is a factor of f(x)
Sine rule to find a length
a/sinA = b/sinB
Sine rule to find an angle
sinB/b = sinC/c
Cosine rule to find a side
a²=b²+c²-2bcCosA
Cosine rule to find an angle
cosA= b²+c²-a²/2bc
Area of a triangle
½absinC
½acsinB
½bcsinA
Pythagoras rules
SOHCAHTOA
sin= opp/hyp
Cos= adj/hyp
Tan= opp/adj
a²+b²=c²
Form of a logarithm
Logₐn=x
ₐ= number
n = answer
x = power
a^x=n
Logs - multiplication law
logₐxy=logₐx+logₐy
Logs - division law
logₐ(x/y)=logₐx-logₐy
Logs - power law
logₐ(x)^k=Klogₐx
logs - negative power law
Logₐ(1/x)= -logₐx
How to solve a^x=b with logs
Take log to base 10 of each side and solve
Change of base rule for logs
logₐx= logₔx/logₔa
ₔ=b
Midpoint of (x₁,y₁) and (x₂,y₂)
x₁+x₂/2, y₁+y₂/2
equation of a circle centre (a,b) and radius r
(X-a)²+(y-b)²=r²
Angles in a semi circle =
90 degrees
Angle between a tangent and a radius=
90 degrees
Conversions for degrees & radians
Degrees –> radians x π/180
Radians –> degrees x 180/π
If a circe has an arc and radius ‘r’ then how big will the angle and the centre be
1 radian
Arc length in radians
L = rθ
Radius x angle at centre
Area of a sector in radians
½r ²θ
½ x radius x radius x angle at centre
Area of a segment in radians
½r ²(θ - sinθ)
0.5 x radius x radius x (angle at centre - SIN angle at centre)
What is common ratio
What you divide/multiply by to get the next term of a geometric series
Nth term of geometric series
arⁿ-¹
First term x (common ratio)ⁿ-¹
Sum to n terms of geometric series
Sn = a(1-rⁿ)/1-r
Sum to infinity of geometric series
S∞= a/1-r
Quadrants that trigonometrical functions are positive
SACT
1st - sin
2nd - sin, cos, tan
3rd - cos
4th - tan
How to solve
Sinθ= 0.3 For 0
1- check if the interval is degrees or radians
2- find the acute angle with sin-¹ to 1.d.p.
3- draw cast diagram with acute angles in for when it will be positive
4- calculate the angles from y=0