How do you calculate the sum of the arithmetic sequence defined by the expression 4n + 10 from n = 1 to n = 18?

To calculate the sum of the finite arithmetic sequence defined by the expression 4n + 10 for values of n ranging from 1 to 18, we first need to derive the terms of this sequence for each integer value of n within that range.

1. **Calculate the terms:** We substitute values of n from 1 to 18 into the expression:

  • For n = 1: 4(1) + 10 = 14
  • For n = 2: 4(2) + 10 = 18
  • For n = 3: 4(3) + 10 = 22
  • For n = 4: 4(4) + 10 = 26
  • For n = 5: 4(5) + 10 = 30
  • For n = 6: 4(6) + 10 = 34
  • For n = 7: 4(7) + 10 = 38
  • For n = 8: 4(8) + 10 = 42
  • For n = 9: 4(9) + 10 = 46
  • For n = 10: 4(10) + 10 = 50
  • For n = 11: 4(11) + 10 = 54
  • For n = 12: 4(12) + 10 = 58
  • For n = 13: 4(13) + 10 = 62
  • For n = 14: 4(14) + 10 = 66
  • For n = 15: 4(15) + 10 = 70
  • For n = 16: 4(16) + 10 = 74
  • For n = 17: 4(17) + 10 = 78
  • For n = 18: 4(18) + 10 = 82

2. **List of the terms:** The generated terms from n = 1 to n = 18 are:

[14, 18, 22, 26, 30, 34, 38, 42, 46, 50, 54, 58, 62, 66, 70, 74, 78, 82]

3. **Sum of the terms:** To find the sum of this sequence, we can use the formula for the sum of an arithmetic sequence:

The formula for the sum S of the first n terms of an arithmetic sequence is given by:

S = (n/2) * (first term + last term)

In our case:

  • n = 18 (the number of terms)
  • first term = 14
  • last term = 82

4. **Applying the formula:** Substituting these values into the formula, we get:

S = (18/2) * (14 + 82)

S = 9 * 96

S = 864

5. **Final Result:** Therefore, the sum of the arithmetic sequence from n = 1 to n = 18 for the expression 4n + 10 is 864.

Leave a Comment