Question

Use the given information to find the exact value of the expression.

sin α = 21/29, α lies in quadrant II, and cos β = 15/17 , β lies in quadrant I Find sin (α - β)

Answer 1

@satellite73

Answer 2

@ganeshie8

Answer 3

draw a triangle, label the sides

Answer 4

Thank you

Answer 5

then you need \(\cos(\alpha)\) which you find via pythagoras

Answer 6

I got 475/493

Answer 7

you mean as a final answer?

Answer 8

i didn't get anywhere near there yet
i am still at \[\cos(\alpha)=-\frac{20}{29}\]

Answer 9

yes

Answer 10

Hints:
1) You're going to need the "difference formula," sin (a-b) = sin a cos b -cos a sin b.
2) From the given info, you're going to need to find \[\cos \alpha~and ~\sin \beta \]

Answer 11

I'd suggest you begin with (2) and then focus on (1).