Use a sum or difference formula to find the exact value of the following.

J Santosh asked Oct 14, 2023

356,001 views

39 votes

J Santosh asked Oct 14, 2023

2.4k points

Your comment on this question:

Email me at this address if a comment is added after mine:Email me if a comment is added after mine

Privacy: Your email address will only be used for sending these notifications.

Email me at this address if my answer is selected or commented on:Email me if my answer is selected or commented on

Privacy: Your email address will only be used for sending these notifications.

21 votes

Given:

$\cos (4\pi)/(7)\cos (11\pi)/(42)-\sin (4\pi)/(7)\sin (11\pi)/(42)$

The sum and difference formula is defined as,

$\begin{gathered} \text{Cos(A}+B)=\cos \text{ A cos B-SinA sinB} \\ \text{Here, A= }\frac{\text{4}\pi}{7}\text{ and B=}(11\pi)/(42) \end{gathered}$

So, for the given expression,

Param answered Oct 20, 2023

by Param

3.0k points

Email me at this address if a comment is added after mine:Email me if a comment is added after mine

Privacy: Your email address will only be used for sending these notifications.

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

1.6m questions

2.0m answers