SOLUTION: calculate the exact value of the following expressions justifying the steps of calculating : Arcsin ( sin (2π/5) ) , Arcsin ( cos ( 3π/7) ) , sin (Arccos (-3/7)) ad

Algebra ->  Trigonometry-basics -> SOLUTION: calculate the exact value of the following expressions justifying the steps of calculating : Arcsin ( sin (2π/5) ) , Arcsin ( cos ( 3π/7) ) , sin (Arccos (-3/7)) ad      Log On


   



Question 1008289: calculate the exact value of the following expressions justifying the steps of calculating :
Arcsin ( sin (2π/5) ) , Arcsin ( cos ( 3π/7) ) , sin (Arccos (-3/7))
ad arccos x = 2Arccos (3/4)

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Arcsin ( sin (2π/5) ) = (2pi/5)
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Arcsin ( cos ( 3π/7) ) = 0.2244
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sin (Arccos (-3/7)) = 0.9035
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arccos x = 2Arccos (3/4)
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Take the cos of both sides to get:
x = 0.125
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