What Is the Angle Between the Unit Vector $\vec { u }$

question 104

Multiple Choice

What is the angle between the unit vector $\vec { u }$ and $\nabla f ( a , b )$ if $f _ { a } ( a , b ) = - 0.5 \| \nabla f ( a , b ) \|$ ?

• A) \(5 \pi / 6\)
• B) \(2 \pi / 3\)
• C) \(\pi / 3\)
• D) \(\pi / 6\)

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Definitions:

Utils

A hypothetical unit of measurement used in economics to quantify the amount of utility or satisfaction gained by consuming goods and services.

Outcomes

The results or effects of actions, decisions, or policies, with a broader application beyond purely economic contexts.

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A preference for certainty over uncertainty with regards to outcomes, particularly in the context of financial decisions.

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An assured or guaranteed stream of income, usually referring to investments with fixed returns.