Prove $\cos \left( x - \frac { \pi } { 2 } \right) + \cos \left( x + \frac { \pi } { 2 } \right) = 0$

question 29

Essay

Prove $\cos \left( x - \frac { \pi } { 2 } \right) + \cos \left( x + \frac { \pi } { 2 } \right) = 0$ .

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Definitions:

Equilibrium

A state in which market supply and demand balance each other, and as a result, prices become stable.

Market Failure

A situation where the allocation of goods and services by a free market is not efficient, often leading to a net social welfare loss.

Property Rights

The rights of owners of valuable items, whether resources or goods, to dispose of those items as they choose.

Economic Signals

Indicators or messages sent by buyers and sellers which reflect the health and trends of an economy or market, influencing decision-making and resource allocation.