1. find dr/d (theta)

r=4-theta^2sin(theta)

and

2.Let x and y be differentiable functions of t, and let s=sqrt(5x^2+y^2) be functions of x and y.

a. How is ds/dt related if y is constant

ds/dt=?dx/dt

b. how is ds/dt related to dx/dt and dy/dt if neither x nor y is constant

ds/dt= ? dx/dt+?dy/dt

c.How is dx/dt related to dy/dt if s is constant

dx/dt=?dy/dt.

HAVE NO IDEA AND NEED HELP, PLEASE AND THANK YOU