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Given the scalar function f(x,y,z)=x2+y.
Step 1: Find the gradient of f.
The gradient of a scalar function f is given by:
∇f=∂x∂fi+∂y∂fj+∂z∂fk
First, calculate the partial derivatives:
∂x∂f=∂x∂(x2+y)=2x
∂y∂f=∂y∂(x2+y)=1
∂z∂f=∂z∂(x2+y)=0
Substitute these into the gradient formula:
∇f=2xi+1j+0k
∇f=2xi+j
The gradient of f is 2xi+j.
Step 2: Find the divergence.
Divergence is defined for a vector field. Assuming the question asks for the divergence of the gradient of f, which is ∇⋅(∇f).
Let F=∇f=2xi+j+0k.
The divergence of a vector field F=Pi+Qj+Rk is given by:
∇⋅F=∂x∂P+∂y∂Q+∂z∂R
Here, P=2x, Q=1, and R=0.
Calculate the partial derivatives:
∂x∂P=∂x∂(2x)=2
∂y∂Q=∂y∂(1)=0
∂z∂R=∂z∂(0)=0
Substitute these into the divergence formula:
∇⋅(∇f)=2+0+0=2
The divergence of the gradient of f is 2.
Step 3: Find the curl.
Curl is defined for a vector field. Assuming the question asks for the curl of the gradient of f, which is ∇×(∇f).
Let F=∇f=2xi+j+0k.
The curl of a vector field F=Pi+Qj+Rk is given by:
∇×F=(∂y∂R−∂z∂Q)i+(∂z∂P−∂x∂R)j+(∂x∂Q−∂y∂P)k
Here, P=2x, Q=1, and R=0.
Calculate the partial derivatives:
∂y∂R=∂y∂(0)=0
∂z∂Q=∂z∂(1)=0
∂z∂P=∂z∂(2x)=0
∂x∂R=∂x∂(0)=0
∂x∂Q=∂x∂(1)=0
∂y∂P=∂y∂(2x)=0
Substitute these into the curl formula:
∇×(∇f)=(0−0)i+(0−0)j+(0−0)k=0i+0j+0k
∇×(∇f)=0
The curl of the gradient of f is 0.
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