Simplify 2/(a^2b^3)-1/(ab)

$\frac{2}{a^{2} b^{3}} - \frac{1}{a b}$

Step 1

To write $- \frac{1}{a b}$ as a fraction with a common denominator, multiply by $\frac{a b^{2}}{a b^{2}}$ .

$\frac{2}{a^{2} b^{3}} - \frac{1}{a b} \cdot \frac{a b^{2}}{a b^{2}}$

Step 2

Write each expression with a common denominator of $a^{2} b^{3}$ , by multiplying each by an appropriate factor of $1$ .

Multiply $\frac{1}{a b}$ by $\frac{a b^{2}}{a b^{2}}$ .

$\frac{2}{a^{2} b^{3}} - \frac{a b^{2}}{a b (a b^{2})}$

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

$\frac{2}{a^{2} b^{3}} - \frac{a b^{2}}{a^{1} a b \cdot b^{2}}$

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

$\frac{2}{a^{2} b^{3}} - \frac{a b^{2}}{a^{1} a^{1} b \cdot b^{2}}$

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

$\frac{2}{a^{2} b^{3}} - \frac{a b^{2}}{a^{1 + 1} b \cdot b^{2}}$

Add $1$ and $1$ .

$\frac{2}{a^{2} b^{3}} - \frac{a b^{2}}{a^{2} b \cdot b^{2}}$

Multiply $b$ by $b^{2}$ by adding the exponents.

Move $b^{2}$ .

$\frac{2}{a^{2} b^{3}} - \frac{a b^{2}}{a^{2} (b^{2} b)}$

Multiply $b^{2}$ by $b$ .

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

$\frac{2}{a^{2} b^{3}} - \frac{a b^{2}}{a^{2} (b^{2} b^{1})}$

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

$\frac{2}{a^{2} b^{3}} - \frac{a b^{2}}{a^{2} b^{2 + 1}}$

Add $2$ and $1$ .

$\frac{2}{a^{2} b^{3}} - \frac{a b^{2}}{a^{2} b^{3}}$

Step 3

Combine the numerators over the common denominator.

$\frac{2 - a b^{2}}{a^{2} b^{3}}$