Choose the One Alternative That Best Completes the Statement or Answers

question 120

Multiple Choice

Choose the one alternative that best completes the statement or answers the question.
Express the product as a sum containing only sines or cosines.
- $\cos \frac { 11 \theta } { 2 } \cos \frac { \theta } { 2 }$

• A) \(\frac { 1 } { 4 } \cos ^ { 2 } ( 5 \theta )\)
• B) \(\frac { 1 } { 4 } [ \cos ( 6 \theta ) - \sin ( 4 \theta ) ]\)
• C) \(\frac { 1 } { 2 } [ \cos ( 2 \theta ) + \cos ( 3 \theta ) ]\)
• D) \(\frac { 1 } { 2 } [ \cos ( 3 \theta ) - \sin ( 2 \theta ) ]\)

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Definitions:

Exponentially Smoothed Forecast

A method of forecasting that gives more weight to recent data points, using exponential smoothing to produce a smoothed time series.

Forecast Error

The difference between the actual value and the predicted value in a forecast, indicating the accuracy of the forecasting process.

Weighting Scheme

A method of assigning different weights or importance to various elements or criteria in order to calculate a composite score or make decisions.

Exponential Smoothing

A technique used in time-series analysis to smooth data and forecast by giving greater weight to more recent observations.