## Calculus 10th Edition

a) $\frac{dy}{dt} = \frac{24}{25}$ in/sec b) $\frac{dy}{dt} = 0$ in/sec c) $\frac{dy}{dt} = -\frac{24}{25}$ in/sec
y = $\frac{1}{1+x^2}$ $\frac{dy}{dt} = -(1+x^2)^-2*(2x) \frac{dx}{dt} = \frac{-2x}{(1+x^2)^2} \frac{dx}{dt}$ when dx/dt = 6 in/sec a) x = -2 $\frac{dy}{dt} = \frac{-2(-2)}{(1+(-2)^2)^2}(6) = \frac{24}{25}$ b)x = 0 $\frac{dy}{dt} = \frac{-2(0)}{(1+(0)^2)^2}(6) = 0$ c) x = 2 $\frac{dy}{dt} = \frac{-2(2)}{(1+(2)^2)^2}(6) =- \frac{24}{25}$