1.an = 3n - 1

2. an = 2(2n - 3)
3.an = 4^n
4.an = (2/3)^n
5. an = (-1)^n(n + 5)
6. an = (-1)^n + 1(n + 6)
7. an= n+3/2n-1
8. a1 = -5 and an = an-1 - 3 for n ≥ 2
9. a1 = -6 and an = -2an-1 for n ≥ 2
10.a1 = 4 and an = 3an-1 + 2 for n ≥ 2
11. Find a8 when a1 = -10, d = -3.

3 points
Question 16


Use the formula for the general term (the nth term) of an arithmetic sequence to find the indicated term of the sequence with the given first term, a1, and common difference, d.

Find a21 when a1 = 28, d = -5.
Answer

-77

128

-100

-72

3 points
Question 17


Write a formula for the general term (the nth term) of the arithmetic sequence. Then use the formula for an to find a20, the 20th term of the sequence.

1, 4, 7, 10, 13, . . .
Answer

an = 3n + 2; a20 = 62

an = n + 3; a20 = 23

an = 3n - 2; a20 = 58

an = 2n - 3; a20 = 37

3 points
Question 18


Write a formula for the general term (the nth term) of the arithmetic sequence. Then use the formula for an to find a20, the 20th term of the sequence.

25, 16 , 7, -2, . . .
Answer

an = -9n + 25; a20 = -155

an = -9n + 34; a20 = -146

an = 9n - 25; a20 = 155

an = 9n - 34; a20 = 146

3 points
Question 19


Solve the problem.

The population of a town is increasing by 200 inhabitants each year. If its population at the beginning of 1990 was 27,842, what was its population at the beginning of 1998?
Answer

222,680 inhabitants

29,442 inhabitants

29,242 inhabitants

445,360 inhabitants

3 points
Question 20


Find the indicated sum.

Find the sum of the first 50 terms of the arithmetic sequence: 3, -4, -11, -18, . . .
Answer

-8600

-8425

-347

-8420

3 points
Question 21


Find the indicated sum.

Find the sum of the first 48 terms of the arithmetic sequence: 2, 4, 6, 8, . . .
Answer

98

2359

2400

2352
Just reply if you can check my work and i will post my answers again

I see problems and answer choices, but I don't see any of your work to check.

How do the first 11 expressions relate to the rest of the post?

Sure, I can check your work. Please post your answers and I will verify them for you.

Sure, I can help you check your work. Please post your answers again, and I will review them for you.