$\"\"$

(a)

Consider two functions $\"\"$ and $\"\"$ .

The function $\"\"$ , it might be discontinuous at $\"\"$ .

The function $\"\"$ is continuous at every value of $\"\"$ .

Therefore the function $\"\"$ and $\"\"$ are equal except at $\"\"$ .

$\"\"$

(b)

Consider two functions $\"\"$ and $\"\"$ .

The function $\"\"$ is discontinuous at $\"\"$ .

The function $\"\"$ is continuous at every value of $\"\"$ .

The functions $\"\"$ and $\"\"$ are equal except at $\"\"$ .

$\"\"$

(a)

The function $\"\"$ and $\"\"$ agree $\"\"$ at all except at one point.

(b)

The two function agree at all except at $\"\"$ .