Arithmetic & geometric sequence
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n-th term29
Sum of first n terms155
First terms2, 5, 8, 11, 14, 17, 20, 23, 26, 29
Worked example
Given: Type = Arithmetic (aₙ = a₁ + (n−1)d); First term a₁ = 2; Difference / ratio = 3; Term number n = 10
Result: n-th term = 29; Sum of first n terms = 155; First terms = 2, 5, 8, 11, 14, 17, 20, 23, 26, 29
How it is calculated
1. Enter the values you know. 2. The calculator converts them to base units and applies the formula. 3. The result is shown in the unit you choose.
Frequently asked questions
How do I calculate it?
Given: Type = Arithmetic (aₙ = a₁ + (n−1)d); First term a₁ = 2; Difference / ratio = 3; Term number n = 10. Result: n-th term = 29; Sum of first n terms = 155; First terms = 2, 5, 8, 11, 14, 17, 20, 23, 26, 29.
Is the calculator free and private?
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