Formulas Flashcards
sinA
opposite/hypotenuse
or
cos(90°-A)
cosA
adjacent/hypotenuse
or
sin(90°-A)
tanA
opposite/adjacent
cscA
hypotenuse/opposite
or
1/sinA
secA
hypotenuse/adjacent
or
1/cosA
cotA
adjacent/opposite
or
1/tanA
sin(-A)
-sinA
cos(-A)
cos(A)
sin2A
2sinAcosA
cos2A
cos2A-sin2A
pythagorean identities
sin2A + cos2A = 1
and
tan2A + 1 = sec2A
1-cos2A=
sin2A
sec2A-1=
tan2A
Area of a circle
Circumference
ArcLength
Asector
A = πr2
C = 2πr = π
ArcLength = (-) / 360 (2πr)
Asector = (-) / 360 (πr2)
Area of a sphere
Volume
A = 4 πr2
V = (4/3)πr3
Area of a cylinder
Volume
A = 2πrh
V = πr2h
Area of an Ellipse
πab
Area of a triangle
(1/2)b•h
Area of a rhombus
b•h
distance
= velocity • time
time
= distance/ velocity
average velocity
= [total distance traveled]/ [total time elasped]
combination formula
the number of ways that r things can be chosen from n things when order does not matter:
C (n,r) = [n!/(n-r)!•r!]
Permutation formula
the number of ways that r things can be chosen from n things when order does matter:
P (n,r) = [n!/(n-r)!]
binomial probability distribution
the probability that there will be exactly r outcomes out of n trials when the probability of success in each trial is uniformly p:
C (n,r)•pr(1-p)n-r
probability dealing with identical
the number of ways that n things can be ordered when a of them are identical, b of them are identical, c of them are identical, etc. (as in the letters in the word TENNESSEE):
n!/(a!•b!•c!•…)
mean of n scores
µ = Σxi/n
variance
σ2 = Σ(xi - µ)2/n
standard deviation
σ =
Empirical Rule
Logbx = n
bn = x
log(A•B) =
log (A) + log (B)