The logical expression

$$

$=$

$$

$+$

$$

$$

$$

Y$=$A$+$

A

B is equivalent to

$$

$=$

$$

$$

Y$=$AB

$$

$=$

$$

$$

$$

Y$=$

A

B

$$

$=$

$$

$$

$+$

$$

Y$=$

A

$+$B

$$

$=$

$$

$+$

$$

Y$=$A$+$B