# How to | Evaluate Infinite Sums and Products

In calculus, infinite sums and products can pose a challenge to manipulate by hand. *Mathematica* can evaluate a huge number of different types of sums and products with ease.

Use Sum to set up the classic sum , with the function to sum over as the first argument. Use *Mathematica*'s usual range notation as the second argument:

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This also works for finite sums like :

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Use 1. to get the decimal representation:

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This checks that :

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Some functions have an infinite sum representation, and *Mathematica* will recognize these. For example :

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Many functions have product representations as well, and *Mathematica* will even recognize these.

Use Product to check , a function found by the mathematician Euler. The arguments of Product have the same form as Sum:

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Even more abstract functions will be recognized; the Product representation of involves the set of prime numbers:

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