## iheartfood 2 years ago sin(3pi/4)=_____ (answer choices attached inside!)

1. Hero

Where are the attachments?

2. iheartfood

sorry right here haha :P answer choceis A,B,C,D from top to bottom :) **my answer: B. sq.rt 2/2 is that right? :)

3. Hero

Are you familiar with the unit circle?

4. iheartfood

yes.. its a circle with the radius of 1 right?

5. Hero

Yes, but we have to figure out the exact value. So, what I would do is convert radians to degrees first. If you let pi = 180, then you will have: sin(3(180)/4) = sin(3(45))

6. Hero

7. iheartfood

ok... :)

8. iheartfood

and they both equal each other!! So is my answer B. then? :)

9. Hero

B is the correct answer, but how did you figure it out?

10. iheartfood

well i used ur hint and plugged it into my calc and they both had .088 as the result and laso b4 that, i did sin3pi/4and i just converted it :) hehe

11. iheartfood

thanks :)

12. Hero

The only thing you need to figure it out is a unit circle. $\sin(135^{\circ}) = \frac{\sqrt{2}}{2}$

13. iheartfood

ok.. thanks :)