Question

Why is inverse secant (-2) = 2pi/3?

Answer 1

`cos((2pi)/3) = -1/2`
`rArr sec((2pi)/3) = -2`
`rArr sec^(-1)(-2) = (2pi)/3`

Explanation:

`(2pi)/3 = pi - pi/3`

`cos = ("adjaqcent")/("hypotenuse")`

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