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Precalculus 2. Today’s Agenda. Sigma Partial Sum Infinite Series Finite Series HW: Worksheet14-2b Arithmetic and Geometric Sequences AND QUIZ corrections!!!. Do Now: take out Quiz #1 from Unit 2 Sequence vs. Series: what do you know? Think, pair, share. CW: Vocab Review - PowerPoint PPT Presentation
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Today’s Vocab:Today’s Agenda Sigma
Partial SumInfinite SeriesFinite Series
HW: Worksheet14-2b Arithmetic and Geometric Sequences
AND QUIZ corrections!!!
1. Do Now: take out Quiz #1 from Unit 22. Sequence vs. Series: what do you
know? Think, pair, share
PRECALCULUS 2
2. CW: Vocab ReviewSigma Notation and the calculator!
3. CW2: Exploration 14-3a: Introduction to Series
SWBAT… Recognize partial sum notation and interpret its meaning Find partial sums of arithmetic and geometric sequences
"The summation from 1 to 4 of 3n":
Sequence vs. Series; Think Pair Share OUT!Sequence:
Series:
Vocabulary
Arithmetic Sequence- each term after the first is found by adding a constant, called the common difference, d, to the previous term
Geometric Sequence – each term after the first is found by MULTIPLYING a constant, called the common ratio, r, to get the next term
Sequence- a set of numbers {1, 3, 5, 7, …}
Terms- each number in a squence
Common Difference- the number added to find the next term of an arithmetic sequence
Common Ratio - number multiplied to find the next term of an geometric sequence
Arithmetic Series- the sum of an arithmetic sequence
Series- the sum of the terms of a sequence {1 + 3 + 5 + … +97}
Sn is often called an nth partial sum, since it can representthe sum of a certain "part" of a sequence.
Sigma Notation – A series can be represented in a compact form,called summation notation, or sigma notation.The Greek capital letter sigma, , is used to indicate a sum.
Geometric Series- the sum of an geometric sequence
B
nn A
a
UPPER BOUND(NUMBER)
LOWER BOUND(NUMBER)
SIGMA(SUM OF TERMS) NTH TERM
(SEQUENCE)
Recognize partial sum notation and interpret its meaning Find partial sums of arithmetic and geometric sequences
Partial Sums are written with a (Sigma) meaning SUM or “add them all up”
So what are we summing?n Sum whatever appears after the
SigmaIn this case, we are summing n
And what is the value of n? 4
1n
n The values are shown below and above
the SigmaWe sum values of n from 1 to 4
S4 is4
1n
n 1 + 2 + 3 + 4 = 10 S4 =
10
Let’s calculate another partial sum manually then confirm our answer using a calculator
5
1
2 1n
n
3 + 5 + 7 + 9 + 11 = 35
S5 = 35
SWBAT… Recognize partial sum notation and interpret its meaning Find partial sums of arithmetic and geometric sequences
Let’s calculate another partial sum manually then confirm our answer using a calculator
5
1
2 1n
n
3 + 5 + 7 + 9 + 11 = 35
S5 = 35
On the Calculator!2nd stat - - go to MATH, pick 5. sum2nd stat – OPS pick 5. SeqThen type in:(3x+2, x, 2, 5))
Try examples on board!
Precalculus 2; November 14th, 2011DO NOW (5-7 min): Take out HW, then:
We will Evaluate the SUM of a SEQUENCE
using SIGMA NOTATION Evaluate the SUM of a FINITE
geometric sequence and an INFINTIE Geometric Sequence!
ANNOUNCEMENT: QUIZ THURSDAY-GEOMETRIC SERIES AND SIGMA NOTATION!!
HW: ch. 11-3 PRACTICE wkst Geo Sequences word problems #s 29-31 AND Geo Series 13-22 ALL and 27 & 28
1,1
)1(1
rr
raS
n
n
Explain WHY in the GEOMETRIC SERIES EQUATION ABOVE, WHY can “r” not equal “1”.
If done, please complete vocabulary match-up.
CW: Geometric FINITE SeriesGeometric INFINITE Series
Geometric Sum Formula for Series
Sum of the nth terms 1st term common ratio nth term
Geometric Sequence VS. Geometric Series1, 3, 9, 27, 81 1 + 3 + 9 + 27 + 81
5, -10, 20, 5 + (-10) + 20
1,1
)1(1
rr
raS
n
n
Find the sum of each geometric series.
1) 7 + 21 + 63 + …, n = 10
2) 2401 – 343 + 49 – …, n = 5
1,1
)1(1
rr
raS
n
n
Find the sum of each geometric series.
3)
4)
7,2
1,161 nra
2,384,31 naa n
1,1
)1(1
rr
raS
n
n
Sum of an Infinite Geometric Series-1 < r < 1
Sum 1st term common ratio
r
aS
1
1