Precalculus: Mathematics for Calculus, 7th Edition

Published by Brooks Cole
ISBN 10: 1305071751
ISBN 13: 978-1-30507-175-9

Chapter 7 - Section 7.3 - Double-Angle, Half-Angle, and Product-Sum Formulas - 7.3 Exercises - Page 561: 40

Answer

$sin\frac{x}{2}=\frac{\sqrt {2-\sqrt 2}}{2}$ $cos\frac{x}{2}=\frac{\sqrt {2+\sqrt 2}}{2}$ $tan\frac{x}{2}=\frac{2-\sqrt 2}{6}$

Work Step by Step

Given $tan(x)=1, 0^\circ\lt x\lt 90^\circ$, we have $cos(x)=\frac{\sqrt 2}{2}$ and $0^\circ\lt \frac{x}{2}\lt 45^\circ$ $sin\frac{x}{2}=\sqrt {\frac{1-cos(x)}{2}}=\sqrt {\frac{2-\sqrt 2}{4}}=\frac{\sqrt {2-\sqrt 2}}{2}$ $cos\frac{x}{2}=\sqrt {\frac{1+cos(x)}{2}}=\frac{\sqrt {2+\sqrt 2}}{2}$ $tan\frac{x}{2}=\frac{sin\frac{x}{2}}{cos\frac{x}{2}}=\sqrt {\frac{2-\sqrt 2}{2+\sqrt 2}}=\frac{2-\sqrt 2}{6}$
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.