document.write( "Question 83716: We are having a lecture this afternoon and I would like to be able to apply the lecture to this so that I can understand it. Thanks for any help.\r
\n" ); document.write( "\n" ); document.write( "1) Use the arithmetic sequence of numbers 1, 3, 5, 7, 9,…to find the following:
\n" ); document.write( "a) What is d, the difference between any two consecutive terms?
\n" ); document.write( "Answer:
\n" ); document.write( "Show work in this space. \r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "b) Using the formula for the nth term of an arithmetic sequence, what is 101st term? Answer:
\n" ); document.write( "Show work in this space. \r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "c) Using the formula for the sum of an arithmetic sequence, what is the sum of the first 20 terms?
\n" ); document.write( "Answer:
\n" ); document.write( "Show work in this space \r
\n" ); document.write( "\n" ); document.write( "d) Using the formula for the sum of an arithmetic sequence, what is the sum of the first 30 terms?
\n" ); document.write( "Answer:
\n" ); document.write( "Show work in this space \r
\n" ); document.write( "\n" ); document.write( "e) What observation can you make about these sums of this sequence (HINT: It would be beneficial to find a few more sums like the sum of the first 2, then the first 3, etc.)? Express your observations as a general formula in \"n.\"
\n" ); document.write( "Answer:
\n" ); document.write( "
\n" ); document.write( "

Algebra.Com's Answer #60205 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
1) Use the arithmetic sequence of numbers 1, 3, 5, 7, 9,…to find the following:
\n" ); document.write( "a) What is d, the difference between any two consecutive terms?
\n" ); document.write( "Answer:
\n" ); document.write( "Show work in this space
\n" ); document.write( "d is the difference between any term and its previous term
\n" ); document.write( "d=3-1 = 2
\n" ); document.write( "----------------------
\n" ); document.write( "b) Using the formula for the nth term of an arithmetic sequence, what is 101st term? Answer:
\n" ); document.write( "Show work in this space. \r
\n" ); document.write( "\n" ); document.write( "nth term = a(n) = a(1)+(n-1)d
\n" ); document.write( "a(101) = 1 + 100*2 = 201
\n" ); document.write( "------------------\r
\n" ); document.write( "\n" ); document.write( "c) Using the formula for the sum of an arithmetic sequence, what is the sum of the first 20 terms?
\n" ); document.write( "Answer:
\n" ); document.write( "Show work in this space
\n" ); document.write( "S(n) = (n/2)(a(1)+a(n))
\n" ); document.write( "S(20) = (20/2)( 1 + a(20))\r
\n" ); document.write( "\n" ); document.write( "S(20) = 10(1+1+19*2)
\n" ); document.write( "S(20 = 10(40) = 400
\n" ); document.write( "--------------------\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "d) Using the formula for the sum of an arithmetic sequence, what is the sum of the first 30 terms?
\n" ); document.write( "Answer:
\n" ); document.write( "Show work in this space
\n" ); document.write( "S(30) = 15(1+1+29*2)
\n" ); document.write( "S(30) = 15(60) = 900
\n" ); document.write( "--------------------\r
\n" ); document.write( "\n" ); document.write( "e) What observation can you make about these sums of this sequence (HINT: It would be beneficial to find a few more sums like the sum of the first 2, then the first 3, etc.)? Express your observations as a general formula in \"n.\"
\n" ); document.write( "Answer:
\n" ); document.write( "The sums are obviously increasing.
\n" ); document.write( "I listed the formula.
\n" ); document.write( "======================
\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.\r
\n" ); document.write( "\n" ); document.write( "
\n" ); document.write( "
\n" );