lets make a thread full of formulas! (1 Viewer)

[danno]

i learn better by writing it down, so here we go:

nth term of arithmetic sequence: Tn = a + (n - 1)d
sum to n terms of arithmetic sequence: Sn = n/2[2a + (n - 1)d] or n/2(a + l)
nth term of geometric sequence: Tn = ar^n-1
sum to n terms of geo sequence: Sn = (a[1 - r^n])/(1 - r)
compound interest: An = P(1 + r/100) where r =interest rate per period, p = principal, An = amount after n years
limiting sum of geo series: S = a/(1 - r)


post any formulas that are important or we could be asked to use.

 

[bloodysunday]

derivative from first principles:
f'(x)=lim h->0 [f(x+h)-f(x)]/h
that came up in my trial so be wary
cosine rule:
a^2=b^2+c^2-2bc*cosA
or
cosA=(b^2+c^2-a^2)/2bc

i dunno those ones just came into my head

 

[Estel]

e = 1 + 1/1! + 1/2! + 1/3!.... = lim n-->infinity (1+1/n)^n
pi^2 = 6 (1/1^2 + 1/2^2.....)
sinx = x + x^3/3! + ...
cosx = 1 + x^2/2! + ...





[sorry i just find ur idea a little silly]

 

[bloodysunday]

hey are those sin and cos ones the taylor series'? we did an assignment on them in 3u term 2

 

[danno]

e = 1 + 1/1! + 1/2! + 1/3!.... = lim n-->infinity (1+1/n)^n
pi^2 = 6 (1/1^2 + 1/2^2.....)
sinx = x + x^3/3! + ...
cosx = 1 + x^2/2! + ...





[sorry i just find ur idea a little silly]

i only did it cause i dont want to go through my whole textbook just so i can remember formulas

 

[bloodysunday]

sin^2)A+cos^2)A=1

w00t

 

[SpaceMonkey]

Product rule:
y = uv
y' = uv' + vu'

Quotient rule:
y = u/v
y' = (vu' - uv')/v^2