Assume that x and y are both differentiable functions of t and the required values of dy/dt and dx/dt
xy=6
a) Find dy/dt, given x=8 and dx/dt=12
b) Find dx/dt, given x=1 and dy/dt=-8
I started with a and got dy/dt=dx/dt(-y/x)
Plugging with the given values leaves me with dy/dt=12(-y/8)
There's a y that is not given, how would I find out y in this case???
3 answers
Finally figured out, simply plug the given x value into the original equation!
This leaves with
dy/dt=12(-.75/8)
dy/dt=-1.125
dy/dt=-9/8
dy/dt=12(-.75/8)
dy/dt=-1.125
dy/dt=-9/8
a) y = 6 x^-1
... dy/dt = -6 x^-2 dx/dt
... dy/dt = (-6 / 64) * 12
b) missing y a typo?
... dy/dt = -6 x^-2 dx/dt
... dy/dt = (-6 / 64) * 12
b) missing y a typo?
2 answers