Solution: The minimum occurs at $ x = -\fracb2a = -\frac-202(5) = 2 $. Verify $ W(2) = 5(4) - 20(2) + 45 = 20 - 40 + 45 = 25 $. The smallest $ x $ is $ \boxed2 $.Question: A hydrologist models groundwater flow with the function $ f(x) = (\sec x + \cos x)^2 + (\csc x - \sin x)^2 $ for $ 0 < x < \frac\pi2 $. Find the minimum value of $ f(x) $. - Portal da Acústica