Mathematics

Question

Which sequence is graphed below?
A. an = n – 2
B. an = n – 1
C. an = n + 1
D. an = n + 2
Which sequence is graphed below? A. an = n – 2 B. an = n – 1 C. an = n + 1 D. an = n + 2

2 Answer

  • Looking at the chart you see that the initial term is -1 and each successive term is 1 more than the previous one.  The rule for nth term of an arithmetic sequence is:

    a(n)=a+d(n-1), a(n)=nth term, a=initial term, d=common  difference, n=term number.

    In this case a=-1 and d=1 so

    a(n)=-1+1(n-1)

    a(n)=-1+n-1

    a(n)=n-2

    So the correct answer is A)
  • The answer is:  [A]:   aₙ = n – 2 " .
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      Explanation:   "aₙ" represents "y" on the "y-axis". 
                          
                             "n" represents "x" on the "x-axis".
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             Considering the answer choices given, one can look at the graph.  When one looks at the graph, when "x = 2, y =0 " ;  or,  when "n = 2, aₙ = 0 ".
       When examining the answer choices, we see that "{Answer choice: [A]" } is the ONLY equation given when these values fit.  Furthermore, by plugging in a few more values on the line, we see that the "equation" in
    "{Answer choice [A] }" makes sense.
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