Answer:
The fourth term of the sequence B(4) =-8
The sequence is 1,-2,4,-8...
Step-by-step explanation:
<u><em>Explanation:-</em></u>
Given that the sequence
B(n) = 1(-2)ⁿ⁻¹
Put n=1
B(1) = 1(-2)¹⁻¹ = 2⁰ =1
Put n=2
B(2) = 1(-2)²⁻¹ = (-2)¹ =-2
Put n=3
B(3) =1(-2)³⁻¹ = (-2)² =4
Put n=4
B(4) = 1(-2)⁴⁻¹ =(-2)³ =-8
The sequence
1,-2,4,-8...
Answer:
0.22
Step-by-step explanation:
In this problem, we divide 12 goldfishes by 45 cubic feet. This is equal to 0.27 goldfish per cubic feet. Answer is A.
0.22
1 75/1000
One and seven thousandth
Step-by-step explanation:
The awnser is -6+6 because it would end up being 0, which is not positive nor negative
Answer:Answer:

Step-by-step explanation:
Given the sequence -4,-6,-8..., in order to get sigma notation to represent the sum of the first seven terms of the sequence, we need to first calculate the sum of the first seven terms of the sequence as shown;
The sum of an arithmetic series is expressed as ![S_n = \frac{n}{2}[2a+(n-1)d]](https://tex.z-dn.net/?f=S_n%20%3D%20%5Cfrac%7Bn%7D%7B2%7D%5B2a%2B%28n-1%29d%5D)
n is the number of terms
a is the first term of the sequence
d is the common difference
Given parameters
n = 7, a = -4 and d = -6-(-4) = -8-(-6) = -2
Required
Sum of the first seven terms of the sequence
![S_7 = \frac{7}{2}[2(-4)+(7-1)(-2)]\\\\S_7 = \frac{7}{2}[-8+(6)(-2)]\\\\S_7 = \frac{7}{2}[-8-12]\\\\\\S_7 = \frac{7}{2} * -20\\\\S_7 = -70](https://tex.z-dn.net/?f=S_7%20%3D%20%5Cfrac%7B7%7D%7B2%7D%5B2%28-4%29%2B%287-1%29%28-2%29%5D%5C%5C%5C%5CS_7%20%3D%20%20%5Cfrac%7B7%7D%7B2%7D%5B-8%2B%286%29%28-2%29%5D%5C%5C%5C%5CS_7%20%3D%20%20%5Cfrac%7B7%7D%7B2%7D%5B-8-12%5D%5C%5C%5C%5C%5C%5CS_7%20%3D%20%5Cfrac%7B7%7D%7B2%7D%20%2A%20-20%5C%5C%5C%5CS_7%20%3D%20-70)
The sum of the nth term of the sequence will be;
![S_n = \frac{n}{2}[2(-4)+(n-1)(-2)]\\\\S_n = \frac{n}{2}[-8+(-2n+2)]\\\\S_n = \frac{n}{2}[-6-2n]\\\\S_n = \frac{-6n}{2} - \frac{2n^2}{2}\\S_n = -3n-n^2\\\\S_n = -n(3+n)](https://tex.z-dn.net/?f=S_n%20%3D%20%5Cfrac%7Bn%7D%7B2%7D%5B2%28-4%29%2B%28n-1%29%28-2%29%5D%5C%5C%5C%5CS_n%20%3D%20%5Cfrac%7Bn%7D%7B2%7D%5B-8%2B%28-2n%2B2%29%5D%5C%5C%5C%5CS_n%20%3D%20%5Cfrac%7Bn%7D%7B2%7D%5B-6-2n%5D%5C%5C%5C%5CS_n%20%3D%20%20%5Cfrac%7B-6n%7D%7B2%7D%20-%20%20%5Cfrac%7B2n%5E2%7D%7B2%7D%5C%5CS_n%20%3D%20-3n-n%5E2%5C%5C%5C%5CS_n%20%3D%20-n%283%2Bn%29)
The sigma notation will be expressed as
. <em>The limit ranges from 1 to 7 since we are to find the sum of the first seven terms of the series.</em>