Question

I have to use sum, difference, product, or half angle formulas for this problem to find the value
sin5pi/8?

Answer 1

I can not get your question, Can you clerify it.

Answer 2

5pi/8 won't break down into addition nicely,\[\Large\rm \frac{5\pi}{8}=\frac{4\pi}{8}+\frac{\pi}{8}\]\[\Large\rm \frac{5\pi}{8}=\frac{2\pi}{8}+\frac{3\pi}{8}\]Both of those options leave us with really bad angles, 3pi/8 and the pi/8.

So we'll have to try using subtraction instead.

Answer 3

thinking...

Answer 4

I really don't think there is a way to make that work.
You instead need to use your Half-Angle Formula.

Example:
If trying to find \(\Large\rm \cos\left(\frac{5\pi}{8}\right)\)
You would instead write it like this: \(\Large\rm \cos\left(\frac{5pi/4}{2}\right)\)

And then apply your formula.

Answer 5

Hmm. Question says added or substracted. So maybe just
\(\huge x=\frac{5\pi}{8}\) and y=0
or viceversa

Answer 6

so x+y=5pi/8
and x-y=5pi/8

Answer 7

It could be something else other than addition and subtraction. I have to use sum, difference, product, or half angle formulas

Answer 8

then I dont understand your question

Answer 9

I'll reword it

Answer 10

think of it this way
you know the sin of 5pi/4 right?

Answer 11

-sqrt 2/2 I'm about to get on the bus for school so I wont be able to reply quickly after this

Answer 12

right
5pi/8 devided by two is 5pi/4
I hope this is enough hint

Answer 13

sery, oposite :)
5pi/4 devided by 2 is 5pi/8