The sum of the sequence -5,-1,3,...125.?

To find the sum of this arithmetic sequence, we first need to determine the common difference between each term.

The common difference is found by subtracting the previous term from the next term.

-1 - (-5) = 4
3 - (-1) = 4
125 - 3 = 122

Since the common difference is 4, we can find the number of terms in the sequence by dividing the difference between the last term and the first term by the common difference and adding 1.

(125 - (-5)) / 4 + 1 = 131 / 4 + 1 = 33

Now we can use the formula for the sum of an arithmetic sequence:

Sum = n/2 * (first term + last term)
Sum = 33/2 * (-5 + 125)
Sum = 16.5 * 120
Sum = 1980

Therefore, the sum of the sequence -5, -1, 3, ... 125 is 1980.

The sequence is: -5,-1,3,...125.?
This is an arithmetic sequence with common difference of 4.
To find the last term, we can use the formula:
nth term = a + (n-1)d
Where a is the first term, d is the common difference and n is the number of terms.

Here, a = -5, d = 4 and n = 32 (since there are 32 terms in the sequence)
Therefore, 125 = -5 + (32-1)4
125 = -5 + 31 - 4
125 = -5 + 124
125 = 119

Hence, the last term of the sequence is 119.

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