Partial Sum Calculator
Use this free Partial Sum Calculator to evaluate the partial sum of a sequence or series. Whether you're working with arithmetic or geometric series, this tool helps you find the sum of the first <em>n</em> terms with step-by-step breakdowns and formulas.
Last Updated: April 15, 2025
What Is a Partial Sum?
A partial sum is the sum of the first n terms of a sequence. It gives a way to approximate infinite series by summing a finite number of initial terms. Partial sums are used in mathematics, physics, and economics to understand series behavior and convergence.
Types of Series You Can Compute
- ➕ Arithmetic series: sums with a constant difference between terms
- ✖️ Geometric series: sums with a constant ratio between terms
- 🔢 Custom numerical series
- ∑ Sigma notation inputs
How to Use the Partial Sum Calculator
- Choose the type of series: arithmetic, geometric, or custom
- Enter the first term, common difference or ratio, and number of terms (n)
- If using sigma notation, input the general term and bounds
- Click "Calculate" to get the partial sum
- View the result with steps and relevant formula used
Partial Sum Examples
- Example 1 (Arithmetic): \( a = 2,\ d = 3,\ n = 5 \) → \( S_5 = \frac{5}{2} \times (2\times2 + (5 - 1)\times3) = 40 \)
- Example 2 (Geometric): \( a = 1,\ r = 2,\ n = 4 \) → \( S_4 = \frac{1(1 - 2^4)}{1 - 2} = 15 \)
- Example 3 (Sigma Notation): \( \sum_{k=1}^{5} (2k + 1) \) → Result: 35
Applications of Partial Sums
- 📈 Approximating infinite series
- 📘 Solving math and calculus problems
- 💰 Analyzing financial models
- 📐 Understanding convergence in sequences
- 🔬 Estimating outcomes in physical sciences
Frequently Asked Questions (FAQ)
What is the difference between a partial sum and a total sum?
A partial sum only includes a finite number of terms, while the total (infinite) sum includes all terms, if it converges.
Can this calculator handle sigma notation?
Yes! Simply enter your formula and limits and let the calculator handle the rest.
Does the calculator show step-by-step solutions?
Absolutely. It explains which formula is used and breaks down the calculation.
Can it work with negative or fractional terms?
Yes, you can use negative, fractional, or irrational values as inputs.
Is this calculator good for geometric series?
Definitely! It's optimized to compute geometric partial sums with speed and clarity.
Start Summing Smarter
Whether you're learning sequences or checking homework, this Partial Sum Calculator helps you quickly find the sum of any series. Get instant answers and better insights into convergence and series behavior.
Try the Calculator Now