If $\mathbf { r } = x \mathbf { i } + y \mathbf { j } + z \mathbf { k }$

question 63

Essay

If $\mathbf { r } = x \mathbf { i } + y \mathbf { j } + z \mathbf { k }$ and $f ( x , y , z ) = \ln | \mathbf { r } |$ , compute $\nabla f$ and determine where $f = 0$ and where $\nabla f = 0$ . What is the domain of f ?

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Definitions:

Disaffirmed

The act of denying, rejecting, or declaring a contract or agreement void, especially in legal contexts involving minors or parties lacking capacity.

Minor

A person who is below the age of majority, legally considered not old enough to take responsibility for legal decisions.

Mental Impairment

A condition that limits a person's intellectual functioning or emotional wellbeing.

Void

A term describing a contract or legal agreement that has no legal force or effect, making it unenforceable by law.