The product rule for exponents states that when we multiply two or more exponents that have the same base, we add the exponents:

a^n\cdot a^m=a^{n+m}

For example,

a^2\cdot a^3 = a^{2+3} = a^5.

To see why the product rule is true, let's take the above example and work it out again, the long way.

For the two factors a^2 and a^3 we have a^2=a\cdot a and a^3= a\cdot a\cdot a. If we now substitute these two expressions into a^2\cdot a^3 , we get the same result: \eqalign{ a^2\cdot a^3&=\\ (a\cdot a) \cdot (a\cdot a\cdot a)&=\\ a\cdot a\cdot a\cdot a\cdot a&=\\ a^5 }

The product rule is just a shortcut for the process above.

FLAG

Simplify a^{9}\cdot a^{7}.

EXPLANATION

We add the exponents, as follows:

\begin{align} a^9\cdot a^7&=\\ a^{9+7}&=\\ a^{16} \end{align}

FLAG

Simplify $z^{17}\cdot z^{5}.$

a
$z^{9}$
b
$z^{22}$
c
$z^{19}$
d
$z^{12}$
e
$z^{25}$

$x^4 \cdot x^3 =$

a
$x^{12}$
b
$x^5$
c
$x^7$
d
$x^3$
e
$x$

Find n such that x^2\cdot x^3 \cdot x^4 = x^n is correct.

EXPLANATION

We add the exponents, as follows:

\begin{align} x^2 \cdot x^3 \cdot x^4&=\\ x^{2+3+4}&=\\ x^9 \end{align}

Therefore x^{n}=x^9 , so n=9.

FLAG

Find $n$ such that $z^5\cdot z^7 \cdot z^{2}=z^{n}$ is correct.

a
$9$
b
$14$
c
$10$
d
$7$
e
$12$

Find $n$ such that $y^2\cdot y^3 \cdot y^{2}=y^{n}$ is correct.

a
$7$
b
$3$
c
$6$
d
$4$
e
$5$

Simplify x\left(x^3 y^5\right) \left(x^2 y^9\right).

EXPLANATION

Here we have two variables, x and y. We will start by grouping the two variables separately: \begin{align} x\left(x^3 y^5\right) \left(x^2 y^9\right) &=\\ x^1\cdot x^3\cdot y^5\cdot x^2\cdot y^9&= \\ \left(x^1\cdot x^3\cdot x^2\right) \left(y^5\cdot y^9\right) \end{align}

This way, we can apply the product rule to the two variables independently: \begin{align} \left(x^1\cdot x^3\cdot x^2\right) \left(y^5\cdot y^9\right)&=\\ x^{(1+3+2)}\cdot y^{(5+9)} &= \\ x^6 y^{14} \end{align}

FLAG

Simplify $(xz)(x^2y^2)(x^3z^3).$

a
$x^6 y^2 z^3$
b
$x^3 y^2 z^3$
c
$x^3 y^3 z^3$
d
$x^6 y^2 z^4$
e
$x^3 y z^2$

Use exponents to rewrite the product $ b \cdot b^2 \cdot c^3 \cdot b^4 \cdot c^5 \cdot c^6 \cdot b^7.$

a
$b^{14}\cdot c^{14}$
b
$b^{18}\cdot c^{11}$
c
$b^{6}\cdot c^{7}$
d
$b^{4}\cdot c^{3}$
e
$b^{7}\cdot c^{6}$
Flag Content
Did you notice an error, or do you simply believe that something could be improved? Please explain below.
SUBMIT
CANCEL