1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
muminat
3 years ago
6

15 points please help

Mathematics
2 answers:
scoundrel [369]3 years ago
4 0

Answer:

Sn = a1 (1-r^n)/ (1-r)

Step-by-step explanation:

The formula for the sum of a geometric sequence summations is given by

Sn = a1 (1-r^n)/ (1-r)

  where a1 is the first term, r is the common ratio and n is the term number we are summing up to

Ber [7]3 years ago
3 0

Hello from MrBillDoesMath!

Answer:

The second choice,   a1 (1-r^n)/(1-r)

Discussion:

Let

S= a1 + a1*r + a1*r^2 +......+a1* r^(n-1)                  (*)

be a geometric series with n terms

Multiply both sides by "r":

Sr = a1*r + a1*r^2 +...        + a1*r^(n-1) + a1*r^(n)    (**)            

Subtracting (*) from (**) gives

S-Sr = a1 - a1*r^(n)

       = a1 ( 1 - r^(n))

As S=Sr = S (1-r)

S (1-r) = a1 ( 1 - r^(n))

Divide both sides by (1-r)

S = a1 ( 1 - r^(n)) /(1-r)

Thank you,

MrB

You might be interested in
Y = 2x - 1 and y = x + 3 find the solution by graphing or substitution
zalisa [80]
The answer is the 3rd one
5 0
3 years ago
Read 2 more answers
Need a lot of helpppp
Ulleksa [173]

Answer:

A

Step-by-step explanation:

A is a triangular prism

5 0
3 years ago
Read 2 more answers
12,14 and 16 are the length of the sides on the triangle
velikii [3]
The answer is B)81.33 square units
5 0
3 years ago
Read 2 more answers
Rosabell had 27 posters for the parade, she droppd 19 while marching in the parade. how many does she hav left.
vaieri [72.5K]
11, rosabell had 11 posters for the parade
8 0
3 years ago
Please help me with this problem and if you can show your work​
ella [17]

Answer:

2.9

just answering wrong because i need points sorry

7 0
3 years ago
Other questions:
  • What is the value of x in the equation 1x - y = 30, when y= 15?
    13·2 answers
  • how many gallons of 80% antifreeze solution must be mixed with 100 gallons of 10% antifreeze to get a mixture that is 70% antifr
    10·1 answer
  • How to turn 62.5% to a fraction
    9·2 answers
  • Find the surface area of an orange with a 3'' radius. 24 sq. in. 36 sq. in. 144 sq. in.
    11·2 answers
  • Kiera baked 30 Oatmeal cookies and 48 chocolate chip cookies to package in plastic containers for her teacher friends at school.
    15·1 answer
  • The sales at a particular bookstore grew from $2104 million in 2000 to $3881 million in 2005. Find an exponential function to mo
    8·1 answer
  • The temperature started at 35 F. If the temperature went down 4°F and then up 2 F, whats is the temperature differe relative to
    7·1 answer
  • Please help!!!!<br><br>CE is tangent to this circle, CD is a radius and ECB=48 what is BAC​
    13·1 answer
  • What is the outlier in the data set shown below?<br><br><br> A. 6<br> B. 36<br> C. 40<br> D. 46
    11·2 answers
  • A cafe only sells two types of sandwiches, turkey and steak. The cafe charges $5 for turkey sandwiches and $6 for steak sandwich
    12·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!