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

question 58

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:

Nominal Variable

A type of variable that represents categories with no intrinsic ordering or rank among them.

Indicator Variables

Binary variables used in regression analysis, taking the value of either 0 or 1 to denote the absence or presence of a categorical effect.

Analysis of Variance

A statistical method used to compare the means of three or more samples to determine if at least one of them is significantly different from the others.

Dummy Variable

A binary variable used in regression analyses to represent categories of a nominal variable.