Projectile motion but with resistive force

[tubworld]

I have this question:

A 10kg projectile is launched with an initial speed of 100m/s at an elevation of 35 degrees. The resistive force is R = -bv , where b =10kg/s.

Determine the horizontal and vertical component coordinates of the projectile as functions of time.

How do I do this?? I urgently need the complete solution to this! Thanx!

 

[LeonhardEuler]

Basically you're looking for a differential equation for the x-component of the velocity. This is not difficult to find because you can work with this component without thinking about the y-component. You know that \vec{R}=-b\vec{v}, so then R_x=-bv_x. You also know that \vec{F}=\vec{R}=m\vec{a}=m\vec{\dot{v}}, so R_x=m\dot{v_x}. Substitute for R. Do you recognize the solution of the differential equation you get?