91Ó°ÊÓ

Find the indicated derivative. $$y=9 x^{4}-28 x^{3} ; y^{\prime \prime \prime}$$

Find the derivative. $$y=-2.4 x^{2}$$

Find the indicated partial derivatives. $$r=\left(s-s t^{2}\right)^{4} ; \quad \frac{\partial r}{\partial s}, \frac{\partial r}{\partial t}$$

Use the four-step process to find the derivative of the dependent variable with respect to the independent variable. $$p=2 q^{2}+7$$

Find the derivative \(d y / d x\). $$y=\left(x-0.4 x^{2}\right)^{4}$$

Find the slope of the tangent line to the surface \(z=2 x^{2} y-y^{3}\) in the plane \(x=2\) at the point (2,3,-3).