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
Phoenix [80]
2 years ago
5

Help ASAP

Mathematics
1 answer:
max2010maxim [7]2 years ago
3 0

Answer:

Step-by-step explanation:

The formula for determining the sum of n terms, Sn of a geometric sequence is expressed as

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

Where

n represents the number of term in the sequence.

a represents the first term in the sequence.

r represents the common ratio.

1) 2 – 4 + 8 – 16 + ...

a = 2

r = - 4/2 = - 2

n = 6

Since r is negative, we would use

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

Therefore, the sum of the first 6 terms, S6 is

S6 = 2(1 - (- 2^6))/(1 - - 2)

S6 = 2(1 - 64)/3 = (2 × - 63)/3

S6 = - 42

2) -2, 6, -18, 54

a = - 2

n = 4

r = 6/- 2 = - 3

S4 = - 2(1 - (- 3^4))/(1 - - 3)

S6 = - 2(1 - 81)/4 = (- 2 × - 80)/4

S6 = 40

3) 1, 2, 4, 8, 16, 32, 64, 128, 256

r = 2/1 = 2

n = 9

a = 1

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

S9 = (1 × 2^9 - 1)/(2 - 1)

S9 = 512 - 1

S9 = 511

You might be interested in
Hello can anyone please help me
____ [38]

Answer:

B.

Step-by-step explanation:

6 0
3 years ago
What is the midpoint between (5,-8) and (2,9)
r-ruslan [8.4K]

Answer:

6.5 and 3.5

Step-by-step explanation:

7 0
3 years ago
Mickey said that 45.7654 rounded to the nearest thousandth is 45.765 and Nicole said that it was 45.766. Who is correct and why?
Nesterboy [21]

Answer:

Mickey

Step-by-step explanation:

Mickey is correct because if you look at the number 45.7654 whenever you round to the nearest thousandth it'll be 45.765

5 is the thousandth place so look to the right. If the number to the right is greater than 5 it'll round to 47.766 but since it's a four ti rounds down.

8 0
2 years ago
Read 2 more answers
HELP WITH VOLUME AND SURFACE AREA!!!!!! WILL MARK BRAINLIEST!!!!!
ArbitrLikvidat [17]

Answer:

Volume is 48 yards cubed

surface area is 96 yards squared

4 0
3 years ago
First twelve mulitples of 4
Pachacha [2.7K]

Answer:

4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48

Step-by-step explanation:

4*1 = 4

4*2 = 8

4*3 = 12

and so on...

5 0
2 years ago
Read 2 more answers
Other questions:
  • Annual rent $ 7,380
    10·1 answer
  • 14 is what percent of 50?
    9·1 answer
  • What is the solution to the system of equations 2x-5y=-5 and x+2y=11?
    12·1 answer
  • Please help me with this question!!!<br><br> A.1/1<br> B.1/3<br> C.3/1<br> D.1/2
    14·1 answer
  • 2^l-3x=1/64<br> Solve for l
    6·1 answer
  • For which values of P and Q does the following equation have infinitely many solutions? 67x+Q=Px+37
    5·1 answer
  • Sudhir bought an almirah for RS 13600 and spent RS 400 on its transportation . He sold it for RS 16800 . find the his gain perce
    7·1 answer
  • List three integers that are between -22 and -10<br> PLEASE HELP ASAP
    14·1 answer
  • Each of 50 guests at a banquet will be served an 8-ounce portion of prime rib. If prime rib has a yield percentage of 60%, how m
    10·1 answer
  • HELPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPP
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!