# Einstein work equation

I have arrived at what appears to be a different equation(from Einstein's original work equation,

W= mc^2(1/sqrt(1 − vt^2/c^2)+1). )
for the total energy of a particle of rest mass m,moving at speed Vt.

My derivation using a universal 2D transformational model is as follows

W = mVt^2/2 +m/3*(2c^2+Vt^2)*sqrt(1-Vt^2/c^2)

which gives the rest energy as 2/3mc^2 and a finite total energy at speed c!!!

I feel the model used to arrive at this equation is interesting, but i might have tripped up on the maths somewhere or is it the use of a 2D model instead of a 3D model?