IDNLearn.com is your go-to resource for finding answers to any question you have. Receive prompt and accurate responses to your questions from our community of knowledgeable professionals ready to assist you at any time.

Evaluate the expression.

[tex]\[
\frac{13!}{11!2!}
\][/tex]

[tex]\[
\frac{13!}{11!2!} = \square
\][/tex]

(Simplify your answer. Type an integer or a fraction.)


Sagot :

To evaluate the expression [tex]\(\frac{13!}{11! \cdot 2!}\)[/tex], let's break down the calculation step-by-step.

First, recall that the factorial of a number [tex]\(n\)[/tex], denoted as [tex]\(n!\)[/tex], is the product of all positive integers up to [tex]\(n\)[/tex]. Therefore:
[tex]\[ 13! = 13 \times 12 \times 11 \times 10 \times 9 \times 8 \times 7 \times 6 \times 5 \times 4 \times 3 \times 2 \times 1 \][/tex]
[tex]\[ 11! = 11 \times 10 \times 9 \times 8 \times 7 \times 6 \times 5 \times 4 \times 3 \times 2 \times 1 \][/tex]
[tex]\[ 2! = 2 \times 1 \][/tex]

Now, we observe that [tex]\(11!\)[/tex] is a common factor both in the numerator and the denominator which allows us to simplify the fraction. We can write:
[tex]\[ 13! = 13 \times 12 \times 11! \][/tex]
Thus, the expression becomes:
[tex]\[ \frac{13!}{11! \cdot 2!} = \frac{13 \times 12 \times 11!}{11! \cdot 2!} \][/tex]

Since [tex]\(11!\)[/tex] appears in both the numerator and denominator, they cancel each other out, leaving:
[tex]\[ \frac{13 \times 12 \times 11!}{11! \cdot 2!} = \frac{13 \times 12}{2!} = \frac{13 \times 12}{2 \times 1} \][/tex]

Now we compute the remaining multiplication and division:
[tex]\[ 13 \times 12 = 156 \][/tex]
[tex]\[ 2 \times 1 = 2 \][/tex]

So,
[tex]\[ \frac{156}{2} = 78 \][/tex]

Therefore, the simplified value of the expression [tex]\(\frac{13!}{11! \cdot 2!}\)[/tex] is:
[tex]\[ 78 \][/tex]

So, [tex]\(\frac{13!}{11!2!} = 78\)[/tex]