Me answer this question so i can move on. give a short explaination so i know what to do on future problems

The graph plots x-values on the horizontal axis. It is the horizontal line labeled "x" at the right side of the graph. Values near zero (small values) are near the y-axis, which is the vertical line labeled "y" at the top. Negative x-values are on the left side of the y-axis.

To answer the question, find small x-values (near the y-axis on the left side) and find the corresponding points on the plot of F(x), the blue curve. You will see they are large negative y-values (well below the x-axis). This observation guides you to select ...
  B. F(x) is a very large negative number.


What to do on future problems: understand what the problem statement is telling you about where to look on the graph, then read the graph.

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step-by-step explanation:

we can analyze the pattern at which the terms increase. let us denote , , , so that we can call

1 the 1st term, 3 the 2nd term, 6 the 3rd term,etc.

note the following:

from the 1st term (1) to the 2nd term (3), we go up by 2,from the 2nd term (3) to the 3rd term (6), we go up by 3from the 3rd term (6) to the 4th term (10), we go up by 4, andfrom the 4th term (10) to the 5th term (15), we go up by 5.

the pattern: to get the next term value, we just add the next term number (e.g. 1st, 2nd, to the previous term value (term values are the given numbers in the question, 1, 3, 6, 10, 15,

from , to get to , we add

from , to get to , we add

etc.

we need to form a recursive formula, a formula that has the next term as a function of the previous term. so a possible recursive formula can be

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