Concise notes and tutorials for continuous learning.

The Fundamental principle of counting (or Multiplication principle) states that: "If an event can…

Given a set of different objects, how may distinct arrangements of the objects are there? For…

Given a set of different items, how may distinct arrangements of items are possible, provided any…

The Pythagoras' theorem (or Pythagorean theorem) states that: "In a right-angled triangle, the…