Find the Interval on Which $f ( x ) = x e ^ { - x }$

question 161

Multiple Choice

Find the interval on which $f ( x ) = x e ^ { - x }$ is increasing.

• A) \(( - \infty , 1 ]\)
• B) \(( - \infty , 2 ]\)
• C) \(( - \infty , 3 ]\)
• D) \([ 1,2 ]\)
• E) \([ 1 , e ]\)
• F) \(( - \infty , e ]\)
• G) \(( - \infty , \infty )\)
• H) \(\left( - \infty , \frac { 1 } { e } \right)\)

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Definitions:

Psychoanalysis

The term Freud used for both his theory of personality and his therapy for the treatment of psychological disorders; the unconscious is the primary focus of psychoanalytic theory.

Free Association

A psychoanalytic technique in which a patient says whatever comes to mind without censorship as a way of exploring the unconscious.

Transference

An emotional reaction that occurs during psychoanalysis, in which the patient displays feelings and attitudes toward the analyst that were present in another significant relationship.

Self-Actualization

The pursuit of self-defined goals for personal fulfillment and growth.