C2 Flashcards
(2/3)^-2 =
(3/2)^2
5^-2 =
1/5^2
A^2/3 =
3sqrrtA^2
Sin graph starts at
0
Sinx +2 starts at
2, jut 2 higher than normal sinx
Sin(x+90d)
Moves 90 to the left (negatively)
3sinx
The crests extend up to 3 instead of 1
A stretch in the y direction factor 3
Sin3x
The crests(positive + negative) are 3 times as small
Stretched in the x direction by a factor of 1/3
Y=f(x) becomes y= -f(x)
The line has been reflected at the x axis
Y=f(x) becomes y= f(-x)
Reflected on the y axis
Sin1/3x
The crests are 3 times as big
Stretch in the x direction factor 3
Y= sinx crosses x axis at
0, 180, 360
When it wants you to evaluate a series
Substitute in the “r”s (1,2,3,4) for given number of terms
Add the terms to find Ur
Number on top of sigma
Number on bottom (r=1)
Number of terms
First number substituted in
Recurrence relation
Type given value of x1=
Then put in equation have ANS instead of Xn
Keep pressing equal sign
(The value for the equation is hen fed back in as the next X1)
Find the limit (convergence) of a sequence
Replace Xn+1 and Xn by L
And find the two limits compare with actual values to find which is right
Un(nth term 1,2,3…)(can be used to find last term) =
a + (n - 1)d
a= first term
d=common difference
(Sum of first n terms) Sn =
n/2 (2a + (n-1)d)
(Sum of first n terms if you know first and last term) Sn =
n/2 (a+l)
Sum of the first n natural numbers (taken from sigma notation) r=
n(n + 1) /2
If r is not 1 you will have to do
[top sigma number]-[bottom -1]
What is n on sigma notation
Number on top
You are given two terms and their values
How to find the common difference
A + (n-1)d
A+ (term-1)difference=value
-simultaneous equation them
Geometric series for Un
Un = ar^n-1
r - common ratio
n- nth term
Sum of the first n terms of a geometric series
Sn
Sn = a(1-r^n) /1-r
Sum to infinity
a/ 1-r
Sum to infinity is not possible if
R<1
What to do when you see a cubic
Find a factor 1 /. -1 first
Then divide by x = 1/ -1
Binomial expansion
A decreases by a power as b increases
Use Pascal’s triangle or nCr to find the number for the front
nCr
n- the power
r- number along (first number is 0)
How to find the sum of integers between two numbers
N/2(a + l) - n/2(a +l)
Sine rule
a/sinA = b/sinB = c/sinC