Question
Use the half-angle identities to find the exact value of each trigonometric expression.$$\sin \frac{3 \pi}{8}$$
Step 1
We can use the half-angle identity for sine, which is $\sin \frac{\alpha}{2} = \pm \sqrt{\frac{1 - \cos \alpha}{2}}$. Here, $\frac{3 \pi}{8}$ is our $\frac{\alpha}{2}$, so $\alpha$ would be $\frac{3 \pi}{4}$. Show more…
Show all steps
Your feedback will help us improve your experience
Babita Kumari and 72 other Precalculus educators are ready to help you.
Ask a new question
Labs
Want to see this concept in action?
Explore this concept interactively to see how it behaves as you change inputs.
Key Concepts
Recommended Videos
Use the half-angle identities to find the exact values of the given functions. $$\sin \left(-\frac{3 \pi}{8}\right)$$
Trigonometric Identities and Equations
Multiple-Angle Identities; Sum and Product Identities
Use the Half-angle Formulas to find the exact value of each expression. $$ \sin \left(-\frac{\pi}{8}\right) $$
Analytic Trigonometry
Double-angle and Half-angle Formulas
Use the Half-angle Formulas to find the exact value of each expression. $$ \cos \left(-\frac{3 \pi}{8}\right) $$
Transcript
18,000,000+
Students on Numerade
Trusted by students at 8,000+ universities
Watch the video solution with this free unlock.
EMAIL
PASSWORD