Question

Help finding exact values.

Answer 1

Find an exact value.

sin 75°

Answer 2

\[\frac{ \sqrt{6}+\sqrt{2} }{ 4 }\]
Is this right?

Answer 3

How did you do it?

Answer 4

It is right, but what kind of help are you looking for?

Answer 5

I do not know how to do it, but looking at a unit circle that seemed correct with where the angle should be. I want to know what equatin to use to get that answer for future use.

Answer 6

Do you know the formula: sin(a+b)=sin(a)cos(b)+cos(a)sin(b)?

Answer 7

Like currently I am stuck on
Find an exact value.

sine of negative eleven pi divided by twelve.\[\sin(-\frac{ 11\pi }{ 12 })\]

Answer 8

I am not familiar with that equation.

Answer 9

OK, that makes it a lot more difficult, I guess.
sin(-11pi/12)=-sin(11pi/12)=-sin(pi/12)=-sin(15°)

Have you been instructed to do these kind of problems in a unit circle?

Answer 10

yes to find the final answer.

Answer 11

OK, I'll try to draw one...

Answer 12

I have a pic in front of me that I drew

Answer 13

I think you try to use "nice numbers" that add or subtract to get 75º
45º + 30º = 75º

Answer 14

now use sin(a+b)= sin(a)cos(b) + cos(a) sin(b)

Answer 15

I already figured that one out. I am working on\[\sin(-\frac{ 11\pi }{ 12 })\]

Answer 16

I (for one) switch to degrees first.

Answer 17

how do I do that?

Answer 18

multiply by 180/pi
you get -165 degrees

that means go clockwise from the x-axis.
as a positive angle it is 360-165= 195 degrees

so you want to find the sin(15) in the 3rd quadrant