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@@ -30,8 +30,8 @@
 * **Math**
   * [Factorial](https://github.com/trekhleb/javascript-algorithms/tree/master/src/algorithms/math/factorial)
   * [Fibonacci Number](https://github.com/trekhleb/javascript-algorithms/tree/master/src/algorithms/math/fibonacci)
-  * [Cartesian Product](https://github.com/trekhleb/javascript-algorithms/tree/master/src/algorithms/math/cartesian-product)
-  * [Power Set](https://github.com/trekhleb/javascript-algorithms/tree/master/src/algorithms/math/power-set)
+  * [Cartesian Product](https://github.com/trekhleb/javascript-algorithms/tree/master/src/algorithms/math/cartesian-product) - product of multiple sets
+  * [Power Set](https://github.com/trekhleb/javascript-algorithms/tree/master/src/algorithms/math/power-set) - all subsets of the set
   * [Permutations](https://github.com/trekhleb/javascript-algorithms/tree/master/src/algorithms/math/permutations) (with and without repetitions)
   * [Combinations](https://github.com/trekhleb/javascript-algorithms/tree/master/src/algorithms/math/combinations) (with and without repetitions)  
   * [Primality Test](https://github.com/trekhleb/javascript-algorithms/tree/master/src/algorithms/math/primality-test) (trial division method)