How do you find the exact value of arcsin(sin((7pi)/3))?

1 Answer
Jul 23, 2015

arcsin(sin((7pi)/3)) = pi/3

Explanation:

As an argument to a trigonometric function:
color(white)("XXXX")(7pi)/3 is equivalent to pi/3
color(white)("XXXX")color(white)("XXXX")(since (7pi)/3 = 2pi+pi/3)

Provided theta is within [0, pi]
color(white)("XXXX")arcsin(sin(theta)) = theta
color(white)("XXXX")color(white)("XXXX")(basic definition)

So
arcsin(sin((7pi)/3))
color(white)("XXXX")= arcsin(sin(pi/3))
color(white)("XXXX")= pi/3