#### WaleedEhsan04

##### New member

- Joined
- May 25, 2018

- Messages
- 1

Hope you are all having a good day. I am going over this question as revision and would like to find out if I am approaching it correctly. The question is the following:

Let F and U be a vector field and a scalar fieldrespectively. For each of the following expressions, state whether it is a scalar field(scalar), a vector field (vector) or an invalid expression (invalid):

• U^2(∇ ×

**F**) · (∇ ·

**F**)

• U(∇ ·

**F**)∇(∇ ·

**F**)

• ∇ × (∇U)

• ∇ × ∇(∇ ·

**F**)

Okay so for the first bullet point U^2 (∇ ×

**F**) · (∇ ·

**F**) my answer is: Vector Field

For the second bullet point U(∇ ·

**F**)∇(∇ ·

**F**) my answer is: Vector Field

For the third bullet point ∇ × (∇U) my answer is: Vector Field

For the fourth bullet point ∇ × ∇(∇ ·

**F**) my answer is: Vector Field

I know that it is unlikely that all of them are a vector field, but can anyone correct me if I am wrong? Any feedback would be appreciated.

Thank you