Sequences #E please help???? THank you so much!!!?

Question

Use the arithmetic sequence of numbers 1, 3, 5, 7, 9,…to find the following:
a) What is d, the difference between any 2 terms?
Answer: 2
Show work in this space.
7-5=2,5-3=2,3-1=2, …………


b) Using the formula for the nth term of an arithmetic sequence, what is 101st term? Answer:201
Show work in this space.2n-1 = 2(201)-1



c) Using the formula for the sum of an arithmetic sequence, what is the sum of the first 20 terms?
Answer:400
Show work in this spacea20=1+(20-1)*2=39 20/2+(1+39)




d) Using the formula for the sum of an arithmetic sequence, what is the sum of the first 30 terms?
Answer:900
Show work in this spacen/2*(a1+a30), a30=1+ (30-1)2=59, 30/2*(1+59)




e) What observation can you make about these sums of this sequence ? Express your observations as a general formula in "n."
Answer:

Answer 1

A. The difference between any two terms = (n+1 ) th term - (n) th term
So, the difference d = 3-1 = 5-3 = 7-5 = 2
Answer d = 2

B.Show work in this space.
Given a = first term = 1
n = 101
d = 2
putting above values in formula 1
nth term = 1 + (101-1) * 2
= 1 + 200 = 201
So, nth term = 201
Found the problems you listed above at website below
http://www.algebra.com/algebra/homework/Sequences-and-series/Sequences-and-series.faq.question.44629.html