Find the Differential of the Function at the Indicated Number $$f ( x ) = 13 \sin x + 4 \cos x ; \quad x = \frac { \pi } { 4 }$$

question 106

Multiple Choice

Find the differential of the function at the indicated number.
$$f ( x ) = 13 \sin x + 4 \cos x ; \quad x = \frac { \pi } { 4 }$$

• A) \(\frac { 9 \sqrt { 2 } } { 2 } d x\)
• B) \(- \frac { 17 \sqrt { 2 } } { 2 } d x\)
• C) \(\frac { 17 \sqrt { 2 } } { 2 } d x\)
• D) \(- \frac { 9 \sqrt { 2 } } { 2 } d x\)

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Definitions:

Henry Murray

An American psychologist best known for his development of the Thematic Apperception Test (TAT) and for his theory of personality, which emphasized the role of needs.

Raymond Cattell

A psychologist known for his work in personality traits, factor analysis, and the development of several personality assessments.

Projective Test

A type of personality test in which the individual interprets ambiguous stimuli, revealing hidden emotions and internal conflicts.

Thematic Apperception Test

A projective psychological test that asks respondents to create stories about ambiguous scenes, used to uncover underlying motives, concerns, and how they see the social world.