#### Answer

Valid. Let P represent the set of polynomial functions.
Let D represent the set of differentiable functions.
Let C represent the set of continuous functions.
The major the minor premises are diagrammed. There is only one way to compose the premises which is also diagrammed.

#### Work Step by Step

Given true premises, the conclusion must be true. There is no way for true premises to result in a false conclusion. Hence the argument is valid.