Precalculus Examples

${(a + 6)}^{4}$

Step 1

Use the binomial expansion theorem to find each term. The binomial theorem states ${(a + b)}^{n} = \sum_{k = 0}^{n} n C k \cdot (a^{n - k} b^{k})$ .

$\sum_{k = 0}^{4} \frac{4!}{(4 - k)! k!} \cdot {(a)}^{4 - k} \cdot {(6)}^{k}$

Step 2

Expand the summation.

$\frac{4!}{(4 - 0)! 0!} {(a)}^{4 - 0} \cdot {(6)}^{0} + \frac{4!}{(4 - 1)! 1!} {(a)}^{4 - 1} \cdot {(6)}^{1} + \frac{4!}{(4 - 2)! 2!} {(a)}^{4 - 2} \cdot {(6)}^{2} + \frac{4!}{(4 - 3)! 3!} {(a)}^{4 - 3} \cdot {(6)}^{3} + \frac{4!}{(4 - 4)! 4!} {(a)}^{4 - 4} \cdot {(6)}^{4}$

Step 3

Simplify the exponents for each term of the expansion.

$1 \cdot {(a)}^{4} \cdot {(6)}^{0} + 4 \cdot {(a)}^{3} \cdot {(6)}^{1} + 6 \cdot {(a)}^{2} \cdot {(6)}^{2} + 4 \cdot {(a)}^{1} \cdot {(6)}^{3} + 1 \cdot {(a)}^{0} \cdot {(6)}^{4}$

Step 4

Simplify each term.

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Step 4.1

Multiply ${(a)}^{4}$ by $1$ .

${(a)}^{4} \cdot {(6)}^{0} + 4 \cdot {(a)}^{3} \cdot {(6)}^{1} + 6 \cdot {(a)}^{2} \cdot {(6)}^{2} + 4 \cdot {(a)}^{1} \cdot {(6)}^{3} + 1 \cdot {(a)}^{0} \cdot {(6)}^{4}$

Step 4.2

Anything raised to $0$ is $1$ .

$a^{4} \cdot 1 + 4 \cdot {(a)}^{3} \cdot {(6)}^{1} + 6 \cdot {(a)}^{2} \cdot {(6)}^{2} + 4 \cdot {(a)}^{1} \cdot {(6)}^{3} + 1 \cdot {(a)}^{0} \cdot {(6)}^{4}$

Step 4.3

Multiply $a^{4}$ by $1$ .

$a^{4} + 4 \cdot {(a)}^{3} \cdot {(6)}^{1} + 6 \cdot {(a)}^{2} \cdot {(6)}^{2} + 4 \cdot {(a)}^{1} \cdot {(6)}^{3} + 1 \cdot {(a)}^{0} \cdot {(6)}^{4}$

Step 4.4

Evaluate the exponent.

$a^{4} + 4 a^{3} \cdot 6 + 6 \cdot {(a)}^{2} \cdot {(6)}^{2} + 4 \cdot {(a)}^{1} \cdot {(6)}^{3} + 1 \cdot {(a)}^{0} \cdot {(6)}^{4}$

Step 4.5

Multiply $6$ by $4$ .

$a^{4} + 24 a^{3} + 6 \cdot {(a)}^{2} \cdot {(6)}^{2} + 4 \cdot {(a)}^{1} \cdot {(6)}^{3} + 1 \cdot {(a)}^{0} \cdot {(6)}^{4}$

Step 4.6

Multiply $6$ by ${(6)}^{2}$ by adding the exponents.

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Step 4.6.1

Move ${(6)}^{2}$ .

$a^{4} + 24 a^{3} + {(6)}^{2} \cdot 6 \cdot {(a)}^{2} + 4 \cdot {(a)}^{1} \cdot {(6)}^{3} + 1 \cdot {(a)}^{0} \cdot {(6)}^{4}$

Step 4.6.2

Multiply ${(6)}^{2}$ by $6$ .

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Step 4.6.2.1

Raise $6$ to the power of $1$ .

$a^{4} + 24 a^{3} + {(6)}^{2} \cdot 6^{1} \cdot {(a)}^{2} + 4 \cdot {(a)}^{1} \cdot {(6)}^{3} + 1 \cdot {(a)}^{0} \cdot {(6)}^{4}$

Step 4.6.2.2

Use the power rule $a^{m} a^{n} = a^{m + n}$ to combine exponents.

$a^{4} + 24 a^{3} + 6^{2 + 1} \cdot {(a)}^{2} + 4 \cdot {(a)}^{1} \cdot {(6)}^{3} + 1 \cdot {(a)}^{0} \cdot {(6)}^{4}$

Step 4.6.3

Add $2$ and $1$ .

$a^{4} + 24 a^{3} + 6^{3} \cdot {(a)}^{2} + 4 \cdot {(a)}^{1} \cdot {(6)}^{3} + 1 \cdot {(a)}^{0} \cdot {(6)}^{4}$

Step 4.7

Raise $6$ to the power of $3$ .

$a^{4} + 24 a^{3} + 216 \cdot {(a)}^{2} + 4 \cdot {(a)}^{1} \cdot {(6)}^{3} + 1 \cdot {(a)}^{0} \cdot {(6)}^{4}$

Step 4.8

Simplify.

$a^{4} + 24 a^{3} + 216 a^{2} + 4 \cdot a \cdot {(6)}^{3} + 1 \cdot {(a)}^{0} \cdot {(6)}^{4}$

Step 4.9

Raise $6$ to the power of $3$ .

$a^{4} + 24 a^{3} + 216 a^{2} + 4 a \cdot 216 + 1 \cdot {(a)}^{0} \cdot {(6)}^{4}$

Step 4.10

Multiply $216$ by $4$ .

$a^{4} + 24 a^{3} + 216 a^{2} + 864 a + 1 \cdot {(a)}^{0} \cdot {(6)}^{4}$

Step 4.11

Multiply ${(a)}^{0}$ by $1$ .

$a^{4} + 24 a^{3} + 216 a^{2} + 864 a + {(a)}^{0} \cdot {(6)}^{4}$

Step 4.12

Anything raised to $0$ is $1$ .

$a^{4} + 24 a^{3} + 216 a^{2} + 864 a + 1 \cdot {(6)}^{4}$

Step 4.13

Multiply ${(6)}^{4}$ by $1$ .

$a^{4} + 24 a^{3} + 216 a^{2} + 864 a + {(6)}^{4}$

Step 4.14

Raise $6$ to the power of $4$ .

$a^{4} + 24 a^{3} + 216 a^{2} + 864 a + 1296$