What is the exact value of sin 120° ? Use a double-angle identity.

Bloke asked May 24, 2023

176,343 views

21 votes

Bloke asked May 24, 2023

by Bloke

2.7k 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

Answer:

(√(3))/(2)

Explanation:

Sine is positive in the second quadrant, so:

$\sin (240^(\circ))/(2)=\sqrt{(1-\cos 240^(\circ))/(2)} \\ \\ =\sqrt{(1.5)/(2)} \\ \\ =√(3/4) \\ \\ =(√(3))/(2)$

Permaquid answered May 28, 2023

2.5k 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