/*! 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 50 Verify the identity. $$\tan \l... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Verify the identity. $$\tan \left(\cos ^{-1} \frac{x+1}{2}\right)=\frac{\sqrt{4-(x+1)^{2}}}{x+1}$$

Short Answer

Expert verified
Yes, the trigonometric identity \( \tan \left(\cos^{-1} \frac{x+1}{2}\right) = \frac{\sqrt{4-(x+1)^{2}}}{x+1} \) holds true.

Step by step solution

01

Expressing \( \tan \) as ratio of sine and cosine and determine \( \cos \cos^{-1} \)

To begin with, one need to remember that \( \tan \theta = \frac{\sin \theta}{\cos \theta} \). So, \( \tan \left(\cos^{-1} \frac{x+1}{2}\right) = \frac{\sin{\left(\cos^{-1} \frac{x+1}{2}\right)}}{\cos{\left(\cos^{-1} \frac{x+1}{2}\right)}} \). Now, use the property of inverse cosine function, that \( \cos \left(\cos^{-1} \alpha\right) = \alpha \), thus the denominator of the fraction is \( \frac{x+1}{2} \).
02

Calculating the value of \( \sin \cos^{-1} \)

To get the numerator of the fraction, one needs to find \( \sin \theta \) when \( \cos \theta = \frac{x+1}{2} \). From the Pythagorean theorem, we have \( \sin^2 \theta + \cos^2 \theta = 1 \). So, after rearranging, \( \sin \theta = \sqrt{1 - \cos^2 \theta} = \sqrt{1 - \left(\frac{x+1}{2}\right)^2} = \sqrt{1 - \frac{(x+1)^2}{4}} = \sqrt{\frac{4-(x+1)^2}{4}} \).
03

Simplify the expression

Now, substitute the sine and cosine values into the expression: \( \tan \left(\cos^{-1} \frac{x+1}{2}\right) = \frac{\sin{\left(\cos^{-1} \frac{x+1}{2}\right)}}{\cos{\left(\cos^{-1} \frac{x+1}{2}\right)}} = \frac{\sqrt{\frac{4-(x+1)^2}{4}}}{\frac{x+1}{2}} \). Simplify the expression to get \( \frac{\sqrt{4-(x+1)^2}}{(x+1)} \), which is the same as the right-hand side of the original identity.

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.