3 sequence and trigonometry

Sequences &Trigonometry 2016

III. Sequences and Trigonometry
PART I: Sequences
Words
Sequence
Progression
Arithmetic sequence
Geometric
Difference
Ratio
Series
Finite
Infinite
Term
First Term
Middle Term
Consecutive Terms
Partial sum

Pronunciation

/'si:kwəns/

Indonesian
Barisan

/ə'rɪθmətɪk 'si:kwəns/

Barisan Aritmatika

/'dɪfrəns/

Beda

/'prə'gre∫n/

Barisan

/dƷɪə'mətrɪk 'si:kwəns/

Barisan Geometri


/'reɪ∫ɪəʊ/

Rasio

/'faɪnaɪt/

Berhingga

/'sɪəri:z/

Deret

/'ɪnfɪnət/

Tak Berhingga

/fɜ:st tɜ:m/

Suku Pertama


/tɜ:m/

Suku

/'mɪdl tɜ:m/

Suku Tengah

/kən'sekjʊtɪv tɜ:mz/
/'pɑ:∫l sΛm/

Suku Berurutan
Jumlah sebagian
(suku)

Example:


An arithmetic sequence is a sequence of the form a, a+d, a+2d, ….




The number a is the first term, and d is the difference of the sequence.



The formula for n-th term of the arithmetic sequence is a + (n-1) d



a1, a2, a3 are the first three terms.



a(n+1)/2 is called middle term.



an and an+1 are two consecutive terms.




For arithmetic sequence a, a+d, a+2d, …, the formula for n-th partial
sum Sn is (n/2)(2a + (n − 1)d)



A geometric sequence is sequence in the form of a, ar, ar2, … where r is
the ratio.



The sum of finite or infinite sequence, a1+a2+ ..., is called series.

1 Sequences &Trigonometry

Sequences &Trigonometry 2016

Practice


Complete the sentences or give short answers.

1. The first 6 terms of the arithmetic sequence 13,7,1,... are ______________.
2. If the 10th term of an arithmetic sequence is 55 and the 2nd term is 7,
then its 1st term is ___.
3. The sum of the first 40 terms of the arithmetic sequence 3,7,11,15.., is
_____.
4. If the third term of a geometric sequence is 20 and the sixth term is 2.5,
then the its common ratio is ______.
5. The ___________________of a geometric sequence whose first term is 2
and ____________ is five are 2, 10, 50, 250, and 1250.
6. The ____________________ of sequence 1,2,4,8,... is 256.
7. If the 3rd term of a geometric sequence is 63/4, and the 6th term is
1701/32, then the 4th term is _________.
8. The sum of 1, 0.5, 0.25, 0.125, .. is ______________.
PART II: Greek Alphabet
Big Letters Small Letters Words
Α
α

alpha
Β

β

beta

Γ

γ

gamma

Δ

δ

delta

Ε


ε

epsilon

Ζ

ζ

zeta

Η

η

eta

Θ

θ


theta

Ι

ι

iota

Κ

κ

kappa

Λ

λ

lamda


Μ

μ

mu

Ν

ν

nu

Ξ

ξ

xi

Ο


ο

Π

π

Pronunciation
/'ælfə/

/'bi:tə/

/'gæmə/
/'deltə/

/'epsilən/
/'ziːtə/

/'iːtə/

/'θiːtə/

/aɪ'əʊtə/

/'kæpə/

/'læmdə/

/'mjuː/

/'njuː/

/'ksaɪ/
omicron /'əʊmɪkrən/
pi
/'paɪ/

2 Sequences &Trigonometry

Sequences &Trigonometry 2016

Ρ

ρ

rh o

Σ

σ

Τ

τ

tau

Υ

υ

upsilon

Φ

φ

phi

Χ

χ

chi

Ψ

ψ

ps i

Ω

ω

omega

sigma

/'rəʊ/

/'sɪgmə/
/'tɑʊ/

/'jʊpsɪlən/
/'faɪ/

/'kaɪ/

/'psaɪ/

/'əʊmɪgə/

PART III: Trigonometry
Words
Trigonometry
Adjacent side
Hypotenuse
Opposite side
Angle

Pronunciation
/trɪgə'nɒmətrɪ/

/ə'dƷeɪsnt saɪd/

Sisi samping

/ɒpəzɪt saɪd/

Sisi depan

/dɪ'gri:z/

Derajat

/'kwɒdrənt/

Kuadran

/rɪ'siprəkl/

Kebalikan

Sisi miring

/haɪ'pɒtənyu:z/

Sudut

/'æŋgl/

Degrees
Period

Periode

/'pɪərɪəd/

Quadrant
Radian

Radian

/'rəɪdɪən/

Reciprocal

Indonesian
Trigonometri

Trigonometric Function
sin

sine

/saɪn/

cos

cos; cosine

/kɒz/;/kɒzaɪn/

tan
se c
csc

tan; tangent
sec;
cosec;

/tæn/;/tændƷənt/
/s e k/

cot

cotangent

/'kəʊtændƷənt /

/'kəʊsek/

Examples:

¬ Trigonometry is the study of angle measurement.
¬ The hypotenuse will always be the longest side, and opposite from the
right angle.

3 Sequences &Trigonometry

Sequences &Trigonometry 2016

¬ The opposite side is the side directly across from the angle you are
considering.

¬ The adjacent side is the side next to angle you are considering.
¬ All functions have positive values for angles in Quadrant I, but only sine
has positive values for angles in Quadrant II.

¬ The sine and cosine functions have the period 2π (3600).
Practice
Fill the table below and say the equation, such as sin(00)=….
Degrees

Radians

0

0

30

π/6

45

π/4

60

π/3

90

π/2

Sin

Cos

Tan

Practice
Read the following expressions.

1. (Formulas for Addition and Subtraction)
sin(A + B) = sin A cos B + cos A sin B
cos(A - B) = cos A cos B + sin A sin B
tan(A + B) = tan A + tan B / (1 - tan A tan B)

2. (Phytagorean Identities)

sin2 θ + cos 2 θ= 1
tan2 θ +=
1 sec 2 θ

3. (Formula for Double Angle)

sin 2A = 2 sin A cos A

4. (Formula for half angle)

cos

5. (Cosine Rule)

a² = b² + c² - 2bc cos A

4 Sequences &Trigonometry

θ
1 + cos θ
= ±
2
2

Sequences &Trigonometry 2016

Exercise

Complete the sentences or give short answers.

1. Tangent has positive values for angles in _______________, and
______________ has positive values for angles in Quadrant IV.
2. The tangent and cotangent functions have the period __________
3. If sin α = 0.8, then the value of sin (180-α) is _________ and the value
of tan α is ______________
4. Without using calculator, find cos(150).
5. Find the values of x for which sin 3x = 0.5 if it is given that 0