Evaluate 1/a+1/b

$\frac{1}{a} + \frac{1}{b}$

Step 1

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

$\frac{1}{a} \cdot \frac{b}{b} + \frac{1}{b}$

Step 2

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

$\frac{1}{a} \cdot \frac{b}{b} + \frac{1}{b} \cdot \frac{a}{a}$

Step 3

Write each expression with a common denominator of $a b$ , by multiplying each by an appropriate factor of $1$ .

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

$\frac{b}{a b} + \frac{1}{b} \cdot \frac{a}{a}$

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

$\frac{b}{a b} + \frac{a}{b a}$

Reorder the factors of $b a$ .

$\frac{b}{a b} + \frac{a}{a b}$

Step 4

Combine the numerators over the common denominator.

$\frac{b + a}{a b}$