Evaluate the Integral $\int \operatorname { coth } ( 9 x ) d x$

question 24

Multiple Choice

Evaluate the integral.
- $\int \operatorname { coth } ( 9 x ) d x$

• A) \(\frac { 1 } { 9 } \ln | \sinh 9 x | + C\)
• B) \(\ln | \sinh 9 x | + C\)
• C) \(\frac { 1 } { 9 } \operatorname { csch } ^ { 2 } 9 x + C\)
• D) \(9 \ln \left( \sinh \frac { x } { 9 } \right) + C\)

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Definitions:

Double Marginalization

A scenario in which two or more firms at different stages of a supply chain apply their own markups, leading to inefficiencies and inflated prices for consumers.

Retail Price

The cost at which goods or services are sold to the public, typically higher than the wholesale price to include a markup for profit.

Manufacturer Markup

The difference between the cost to produce a good and its selling price, often added by manufacturers to cover costs and generate profit.

Exclusion of Markup

The practice of not including an additional amount to the cost of goods when pricing them, often to maintain competitive pricing.