SOLUTION: Calculate: sin(α−β), if sin α=− 2/5, cosβ=− 1/3, 3π/2<α<2π, π/2 <β<π
My answer is ((2 root 42)-2)/15 but I
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Question 1125345: Calculate: sin(α−β), if sin α=− 2/5, cosβ=− 1/3, 3π/2<α<2π, π/2 <β<π
My answer is ((2 root 42)-2)/15 but I don't think it is right
Answer by solver91311(24713) (Show Source): You can put this solution on YOUR website!
You think correctly.
is not the correct answer.
\ =\ \frac{2\ -\ 2\,\sqrt{42}}{15})
is the correct answer. Your arithmetic was good, but somewhere you made an error with your signs. Double check your work. Remember that the cosine is positive in the 1st and 4th quadrants, and the sine is positive in the 1st and 2nd quadrants.
John
My calculator said it, I believe it, that settles it
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