Chapter 7: Q. 50 (page 486)

In Problems47–72, establish each identity.
$\cos (π - θ) = - \cos θ$

Short Answer

Expert verified

The given identity is established.

Step by step solution

Step 1. Given Information

We are given an identity,

$\cos (π - θ) = - \cos θ$

Step 2. Establishing the identity

We will establish the given expression as an identity by simplifying one side to give the other side.

Using $\cos (α - β) = \cos α \cos β + \sin α \sin β$ , we get

$\cos (π - θ) = \cos π \cos θ + \sin π \sin θ \cos (π - θ) = (- 1) \times \cos θ + 0 \times \sin θ \cos (π - θ) = - \cos θ$

The given identity is established.

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In Problems47–72, establish each identity.
$\cos (π - θ) = - \cos θ$

Short Answer

Step by step solution

Step 1. Given Information

Step 2. Establishing the identity

One App. One Place for Learning.

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In Problems47–72, establish each identity.cos(π-θ)=-cosθ

Short Answer

Step by step solution

Step 1. Given Information

Step 2. Establishing the identity

One App. One Place for Learning.

Most popular questions from this chapter

Recommended explanations on Math Textbooks

Geometry

Statistics

Logic and Functions

Applied Mathematics

Mechanics Maths

Probability and Statistics

Study anywhere. Anytime. Across all devices.

In Problems47–72, establish each identity.
$\cos (π - θ) = - \cos θ$