
William W. answered 11/07/23
Top Pre-Calc Tutor
Because tangent is the trig ratio opp/adj then "tan^-1(u/sqrt(25-u^2))" is talking about the angle for which the opposite is u and the adjacent is √(25 - u2) so like this:
To take the sine, you must know the hypotenuse (because sin(θ) = opp/hyp)
To find the hypotenuse, use the Pythagorean Theorem:
hyp2 = u2 + (√(25 - u2))2
hyp2 = u2 + 25 - u2
hyp2 = 25
hyp = 5
So the sine of that angle is u/5