$\text { Find the indefinite integral by making the substitution } x = 3 \sec \theta \text {. }$

question 65

Multiple Choice

$\text { Find the indefinite integral by making the substitution } x = 3 \sec \theta \text {. }$ $$\int \frac { x ^ { 3 } } { \sqrt { x ^ { 2 } - 9 } } d x$$

• A) \(\frac { \sqrt { x ^ { 2 } - 9 } ( x + 9 ) } { 3 } + C\)
• B) \(\frac { \sqrt { x ^ { 2 } - 9 } \left( x ^ { 2 } + 18 \right) } { 3 } + C\)
• C) \(\frac { \sqrt { x ^ { 2 } - 9 } \left( x ^ { 2 } + 18 \right) } { 2 } + C\)
• D) \(\frac { \sqrt { x ^ { 2 } - 9 } \left( x ^ { 2 } + 9 \right) } { 3 } + C\)
• E) \(\frac { \sqrt { x ^ { 2 } - 9 } ( x + 18 ) } { 3 } + C\)

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Definitions:

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The outer layer of the adrenal glands, which produces essential hormones such as cortisol, aldosterone, and androgens.

Paracrine Secretion

A form of cell signaling in which the target cell is close to the signal-releasing cell, involving substances that exert their effects only on neighboring cells.

Interstitial Fluid

The fluid that surrounds the cells in tissues, providing nutrients and removing waste.

Neighboring Cells

Cells that are situated close to each other, often sharing a similar function or contributing to the same biological process.