Final answer:
To find dz/dt, we use the chain rule to find the derivatives of x and y with respect to t, and then substitute these values into the equation for dz/dt. Finally, we can calculate the value of dz/dt at t = pi/4.
Step-by-step explanation:
To find dz/dt using the chain rule, we need to find the derivatives of x and y with respect to t and then substitute these values into the given equation for dz/dt.
We have x = e^(5t), so dx/dt = 5e^(5t).
We have y = sin(2t), so dy/dt = 2cos(2t).
Substituting these derivatives into the equation dz/dt = (dz/dx)(dx/dt) + (dz/dy)(dy/dt), we have dz/dt = 20(t^19/e^10t)(5e^(5t)) - 10(t^9e^10t/sin^11(2t))(2cos(2t)).
Substituting t = pi/4, we can calculate the value of dz/dt.