i want to solve second differential equation by ode45

this is my function

(- bc*m*cos(fi)*dfi^2 + ab*m*cos(theta)*dtheta^2 + F - dv*m)/(bc*m*sin(fi))

m=20; ab=0.3; bc=0.6

F=10sin(100*t)

i want realtion plot between(fi/t).&(theta/t)&,(v/t)

[madhan ravi]

what have you tried so far ? upload the equations as latex three equations separately don’t combine them