RegentsReferenceSheeet

Algebra 2/Trigonometry Reference Sheet
Area of a Triangle
1 ab sin C
K=_
2
Functions of the Sum of Two Angles
Law of Cosines
sin (A + B) = sin A cos B + cos A sin B
cos (A + B) = cos A cos B – sin A sin B
tan A + tan B
tan (A + B) = ___________
1 – tan A tan B
sin 2A = 2 sin A cos A
cos 2A = cos2 A – sin2 A
cos 2A = 2 cos2 A – 1
cos 2A = 1 – 2 sin2 A
Functions of the Difference of Two Angles
2 tan A
tan 2A = _______
1 – tan2 A
a 2 = b 2 + c 2 – 2bc cos A
Functions of the Double Angle
sin (A – B) = sin A cos B – cos A sin B
cos (A – B) = cos A cos B + sin A sin B
tan A – tan B
tan (A – B) = ____________
1 + tan A tan B
Functions of the Half Angle
_________
sin _1
2
Law of Sines
b = ____
c
a = ____
____
sin A sin B sin C
_________
1 – cos A
tan A = ± _______
1 + cos A
1
_
2
Sum of a Finite Geometric Series
a 1(1 – r n)
_______
Sn =
1–r
Binomial Theorem
(a + b)n = nC0anb0 + nC1an – 1b1 + nC2an – 2b2 + ... + nCna0bn
n
(a +
=
∑
n – rbr
nC r a
r=0
Algebra 2/Trigonometry Sampler – Fall ’09
_________
+ cos A
cos _1 A = ± 1_______
2
2
Sum of a Finite Arithmetic Series
n(a1 + an)
Sn = _______
2
b)n
√
√
√
– cos A
A = ± 1_______
2
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