Solve the Equation by Making an Appropriate Substitution $\mathrm { x } ^ { 1 / 2 } - 10 \mathrm { x } ^ { 1 / 4 } + 21 = 0$

question 55

Multiple Choice

Solve the equation by making an appropriate substitution.
- $\mathrm { x } ^ { 1 / 2 } - 10 \mathrm { x } ^ { 1 / 4 } + 21 = 0$

• A) \(\{ 81,2401 \}\)
• B) \(\{ 9,49 \}\)
• C) \(\{ - 3 , - 7 \}\)
• D) \(\{ 3,7 \}\)

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Definitions:

Pleasure Principle

A psychoanalytic concept proposing that instinctual drives seek immediate gratification to relieve internal tensions.

Reality Principle

A psychoanalytic concept that represents the ability of the mind to assess the external world and act upon it accordingly, often as a counterbalance to the pleasure principle.

Id

In psychoanalysis, the part of the mind responsible for basic instincts and drives.

Sexual Drive

Sexual drive, or libido, is an individual's overall sexual desire or desire for sexual activity.