Lorentz transform for acceleration

derivating a from v (lorentz transform)
u is the velocity in the +x direction
u=(u-v)/(1-vu/c^2)

a=du/dt

dt=I know
du=?

Differentiate $$v$$ and also $$t$$ in the Lorentz transformations, divide the equation for $$dv$$ by the equation for $$dt$$ and simplify, you should be able to get the expression for the acceleration in an accerated frame.