Use the Derivative Of $f ( x ) = 3 x ^ { 3 } + 9 x$

question 64

Multiple Choice

Use the derivative of $f ( x ) = 3 x ^ { 3 } + 9 x$ to determine any points on the graph of $f ( x )$ at which the tangent line is horizontal.

• A) \(( 1,12 )\)
• B) \(( 1,12 )\) and \(( - 1 , - 12 )\)
• C) \(( 3,108 )\) and \(( - 3,108 )\)
• D) \(( 0,0 )\)
• E) \(f ( x )\) has no points with a horizontal tangent line.

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Definitions:

Direct Labor Rate Variance

The difference between the actual labor cost incurred and the expected (or standard) labor cost for the actual production level.

Direct Labor Variances

The differences between the budgeted and actual labor costs incurred during a production process, analyzed to control and optimize labor expenses.

Research Development

The systematic activity combining both basic and applied research, aimed at discovering solutions to problems or creating new goods and knowledge.

Fixed Overhead Rate

A predetermined rate used to assign fixed manufacturing overhead costs to products, typically based on a standard activity level.