Factorials - Math
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Find the value of:

Find the value of:
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The factorial sign (!) just tells us to multiply that number by every integer that leads up to it. So,
can also be written as:

To make this easier for ourselves, we can cancel out the numbers that appear on both the top and bottom:

The factorial sign (!) just tells us to multiply that number by every integer that leads up to it. So, can also be written as:
To make this easier for ourselves, we can cancel out the numbers that appear on both the top and bottom:
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What is the value of
?
What is the value of ?
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! is the symbol for factorial, which means the product of the whole numbers less than the given number.
Thus,
.
! is the symbol for factorial, which means the product of the whole numbers less than the given number.
Thus, .
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What is the value of
?
What is the value of ?
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By definition,
.
By definition, .
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Stewie has
marbles in a bag. How many marbles does Stewie have?
Stewie has marbles in a bag. How many marbles does Stewie have?
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Simplifying this equation we notice that the 3's, 2's, and 1's cancel so

Alternative Solution

Simplifying this equation we notice that the 3's, 2's, and 1's cancel so
Alternative Solution
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Which of the following is equivalent to
?
Which of the following is equivalent to ?
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This is a factorial question. The formula for factorials is
.

This is a factorial question. The formula for factorials is .
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Which of the following is NOT the same as
?
Which of the following is NOT the same as ?
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The
cancels out all of
except for the parts higher than 4, this leaves a 6 and a 5 left to multilpy 
The cancels out all of
except for the parts higher than 4, this leaves a 6 and a 5 left to multilpy
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Find the value of:

Find the value of:
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The factorial sign (!) just tells us to multiply that number by every integer that leads up to it. So,
can also be written as:

To make this easier for ourselves, we can cancel out the numbers that appear on both the top and bottom:

The factorial sign (!) just tells us to multiply that number by every integer that leads up to it. So, can also be written as:
To make this easier for ourselves, we can cancel out the numbers that appear on both the top and bottom:
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Simplify the following expression:

Simplify the following expression:
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Recall that
.
Likewise,
.
Thus, the expression
can be simplified in two parts:

and

The product of these two expressions is the final answer: 
Recall that .
Likewise, .
Thus, the expression can be simplified in two parts:
and
The product of these two expressions is the final answer:
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To simplify this, just write out each factorial:

To simplify this, just write out each factorial:
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If
is a postive integer, which of the following answer choices is a possible value for the expression.
If is a postive integer, which of the following answer choices is a possible value for the expression.
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This expression of factorials reduces to (n+1)(n+2). Therefore, the solution must be a number that multiplies to 2 consecutive integers. Only 30 is a product of 2 consecutive integers. 
So n would have to be 4 in this problem.
This expression of factorials reduces to (n+1)(n+2). Therefore, the solution must be a number that multiplies to 2 consecutive integers. Only 30 is a product of 2 consecutive integers.
So n would have to be 4 in this problem.
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Divide
by 
Divide by
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A factorial is a number which is the product of itself and all integers before it. For example 
In our case we are asked to divide
by
. To do this we will set up the following:

We know that
can be rewritten as the product of itself and all integers before it or:

Substituting this equivalency in and simplifying the term, we get:

A factorial is a number which is the product of itself and all integers before it. For example
In our case we are asked to divide by
. To do this we will set up the following:
We know that can be rewritten as the product of itself and all integers before it or:
Substituting this equivalency in and simplifying the term, we get:
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Simplify:

Simplify:
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Remember what a factorial is, and first write out what the original equation means. A factorial is a number that you multiply by all whole numbers that come before it until you reach one.
You can simplify because all terms in the expression 17! are found in 20!.
Thus:


Remember what a factorial is, and first write out what the original equation means. A factorial is a number that you multiply by all whole numbers that come before it until you reach one.
You can simplify because all terms in the expression 17! are found in 20!.
Thus:
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Simplify: 
Simplify:
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Rewrite the factorials in multiplicative order.

In this scenario, the numbers of the factorial in the numerator and denominator CANNOT cancel. Simplify by multiplying out the factorials.

Rewrite the factorials in multiplicative order.
In this scenario, the numbers of the factorial in the numerator and denominator CANNOT cancel. Simplify by multiplying out the factorials.
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Simplify the following expression:

Simplify the following expression:
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n! indicates a factorial, which means the products of numbers from 1 to n.



n! indicates a factorial, which means the products of numbers from 1 to n.
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Divide: 
Divide:
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Write out the terms for the factorial.

Cancel out the common numbers in the numerator and denominator.

The answer is
.
Write out the terms for the factorial.
Cancel out the common numbers in the numerator and denominator.
The answer is .
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Multiply: 
Multiply:
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To evaluate the product of these factorials, we will need to expand the factorials.

Multiply all the values.

The answer is: 
To evaluate the product of these factorials, we will need to expand the factorials.
Multiply all the values.
The answer is:
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Divide: 
Divide:
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Expand the factorials in the numerator and denominator.

The terms 1, 2, 3, and 4 can be eliminated from the numerator and denominator. The simplification becomes:

Expand the factorials in the numerator and denominator.
The terms 1, 2, 3, and 4 can be eliminated from the numerator and denominator. The simplification becomes:
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Solve: 
Solve:
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Evaluate the factorials first.


Substitute the values back into the expression.

Simplify the numerator.

Evaluate the factorials first.
Substitute the values back into the expression.
Simplify the numerator.
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Solve the factorial: 
Solve the factorial:
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Evaluate each factorial inside the parentheses.
Zero factorial is equal to
. Simplify by order of operations.

The answer is
.
Evaluate each factorial inside the parentheses.
Zero factorial is equal to . Simplify by order of operations.
The answer is .
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Simplify the following factorial:

Simplify the following factorial:
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Simplify the following factorial:

To solve this, we need to understand factorials. Factorials are denoted by a number followed by the ! sign. What a factorial is, is a given number multiplied by each positive integer leading up to the given number. Stated differently...

So what we have above is really:

Now, because numbers 1 through 14 are in the numerator and the denominator, they will cancel and we will be left with:

Simplify the following factorial:
To solve this, we need to understand factorials. Factorials are denoted by a number followed by the ! sign. What a factorial is, is a given number multiplied by each positive integer leading up to the given number. Stated differently...
So what we have above is really:
Now, because numbers 1 through 14 are in the numerator and the denominator, they will cancel and we will be left with:
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