Math Problem Statement

Use the formulas for lowering powers to rewrite the expression in terms of the first power of cosine: \( \cos^4(x) \sin^2(x) \).

Solution

To rewrite the expression cos4(x)sin2(x)\cos^4(x) \sin^2(x) in terms of the first power of cosine, we can use the power-reducing identities:

  1. For cos2(x)\cos^2(x): cos2(x)=1+cos(2x)2\cos^2(x) = \frac{1 + \cos(2x)}{2}
  2. For sin2(x)\sin^2(x): sin2(x)=1cos(2x)2\sin^2(x) = \frac{1 - \cos(2x)}{2}

Applying these identities, we have: cos4(x)=(cos2(x))2=(1+cos(2x)2)2=(1+cos(2x))24\cos^4(x) = \left(\cos^2(x)\right)^2 = \left(\frac{1 + \cos(2x)}{2}\right)^2 = \frac{(1 + \cos(2x))^2}{4} sin2(x)=1cos(2x)2\sin^2(x) = \frac{1 - \cos(2x)}{2}

Now, we can rewrite the expression: cos4(x)sin2(x)=(1+cos(2x))241cos(2x)2\cos^4(x) \sin^2(x) = \frac{(1 + \cos(2x))^2}{4} \cdot \frac{1 - \cos(2x)}{2} =(1+cos(2x))2(1cos(2x))8= \frac{(1 + \cos(2x))^2 (1 - \cos(2x))}{8}

Now expand and simplify:

  1. Would you like a detailed step-by-step expansion?
  2. Do you want to learn how the identities are derived?
  3. Are you interested in examples with other trigonometric functions?
  4. Should we explore this approach with integrals?
  5. Do you need help with similar power-reduction problems?

Tip: Familiarizing yourself with trigonometric identities can simplify many problems in calculus and trigonometry.

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Math Problem Analysis

Mathematical Concepts

Trigonometry
Power-Reducing Identities

Formulas

\( \cos^2(x) = \frac{1 + \cos(2x)}{2} \)
\( \sin^2(x) = \frac{1 - \cos(2x)}{2} \)

Theorems

Power-Reducing Formulas in Trigonometry

Suitable Grade Level

Grades 11-12