Evaluate the derivative of the function below at the point (ð/3, 9.301). (Round to three decimal places.)

y= (9/x) + ((cosx)^.5)

1 answer

y = 9/x + sqrt(cos x)
y' = -9/x^2 - .5sin x/sqrt(cos x)
y'(pi/3) = -9/(pi^2/9) - .5*sqrt(3)/2 / sqrt(.5)
= -81/pi^2 - sqrt(6)/4
= -8.819