/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 82 Use the product-to-sum formulas ... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Use the product-to-sum formulas to write the product as a sum or difference. $$4 \cos \frac{\pi}{3} \sin \frac{5 \pi}{6}$$

Short Answer

Expert verified
The product can be written as the difference -1.

Step by step solution

01

Identify the relevant parts

In the expression \(4 \cos \frac{\pi}{3} \sin \frac{5 \pi}{6}\), \(\frac{\pi}{3}\) corresponds to \(a\) and \(\frac{5 \pi}{6}\) corresponds to \(b\) if compared to the formula \(\cos a \sin b = \frac{1}{2}[\sin(a+b)-\sin(a-b)]\).
02

Apply the product-to-sum formula

Substitute the values of \(a\) and \(b\) into the formula \(\cos a \sin b = \frac{1}{2}[\sin(a+b)-\sin(a-b)]\) and multiply the expression by the constant, 4. You should now have \(4 \cos \frac{\pi}{3} \sin \frac{5 \pi}{6}=2[\sin(\frac{\pi}{3} + \frac{5 \pi}{6})-\sin(\frac{\pi}{3} - \frac{5 \pi}{6})]\)
03

Simplify the expression

First, simplify within the parentheses to get \(2[\sin(\frac{3 \pi}{2})-\sin(-\frac{\pi}{6})]\). Then, use the identities \(\sin(\frac{3 \pi}{2}) = -1\) and \(\sin(-\frac{\pi}{6}) = -\frac{1}{2}\) to further simplify the expression. This gives \(2[-1-(-\frac{1}{2})]\), which simplifies to \(-1\).

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Study anywhere. Anytime. Across all devices.