If you jump from a window that is 2 meters up you will most likely break the bones in your legs when you land however on a trampoline people can jump up to 6 meters without getting hurt explain why this is true?

The de-acceleration or negative acceleration of stopping is what damages bones. The ground is rigid and therefore the change in momentum when striking the ground will be large. On the trampoline, the elasticity of the material means that the momentum changes more slowly, resulting in smaller accelerations.