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Ontario Tech acknowledges the lands and people of the Mississaugas of Scugog Island First Nation.

We are thankful to be welcome on these lands in friendship. The lands we are situated on are covered by the Williams Treaties and are the traditional territory of the Mississaugas, a branch of the greater Anishinaabeg Nation, including Algonquin, Ojibway, Odawa and Pottawatomi. These lands remain home to many Indigenous nations and peoples.

We acknowledge this land out of respect for the Indigenous nations who have cared for Turtle Island, also called North America, from before the arrival of settler peoples until this day. Most importantly, we acknowledge that the history of these lands has been tainted by poor treatment and a lack of friendship with the First Nations who call them home.

This history is something we are all affected by because we are all treaty people in Canada. We all have a shared history to reflect on, and each of us is affected by this history in different ways. Our past defines our present, but if we move forward as friends and allies, then it does not have to define our future.

Learn more about Indigenous Education and Cultural Services

Factorial

Introduction

The factorial of a nonnegative integer, n, is denoted by: n! and represents the product of all the positive integers less than or equal to n. By definition, 0!=1 and 1!=1.

Example: Find 5!

Solution:

5! = (5)(4)(3)(2)(1)

     = 120

Example: Find 10!

Solution:

10! = (10)(9)(8)...(3)(2)(1)

       = 3628800

Why is this important?

You might encounter factorials when studying probability, Taylor series (in a calculus class), or in a discrete mathematics course. 

Using Your Calculator

A standard scientific calculator should have a button on it (labeled n!) that calculates factorials. Depending on your calculator, you may need to hit this button before or after you enter the number whose factorial you wish to find. On some calculators, you may also have to hit the "2nd function" key, sometimes labeled "INV". To make sure you're using your calculator correctly, try finding 5!...you should get an answer of 120.