How I can plot new variable numerically?

Hi

I have the following system of differential equations and want to solve it numerically (will ode45 works for this system or not?)

dx/dt=a1*x*y*sin(z)

dy/dt=-a2*x^2*sin(z+b*t)

dz/dt=2*a1*y*cos(z)-a2*(x^2/y)*cos(z+b*t)+c

with

x^2+m*y^2=n

initial values: x(0)=q, y(0)=0, z(0)=0

where a1, a2, b, c, m, n, q are constants.

t varies from 0 to 100

How I can plot R=(x^2/(x^2+y^2)) as a function of t?

Yours sincerely,