Question 448516
sin(Arccos(-2/5))
---------------
The point is on a circle of radius 5, and the x value is -2
It's the 2nd quadrant (the principal value).
Find the y value.
{{{y^2 = 5^2 - 2^2 = 21}}}
y = sqrt(21)
{{{sine = sqrt(21)/5}}}