Given that E2 = c2p2 + mo2c4-----------(1); where p represents the relativistic momemtum p=[tex]\gamma[/tex]mou, show that m=(p2c2-T2)/(2Tc2) where m is the relativistic mass of the particle,and T it's kinetic energy. 2. Relevant equations E= T+moc2-------(2) 3. The attempt at a solution I start by saying p2c2= E2-mo2c4 (from (1)), subtracting T2 from both sides gives p2c2 -T2 = E2-mo2c4-T2 . Now using (2) i expand E; p2c2 -T2= (T+moc2)2-mo2c4 -T2 which gives p2c2 -T2= T2+2Tmoc2+mo2c4 -mo2c4 -T2; simplifying p2c2 -T2 = 2Tmoc2 Now dividing by 2Tc2 gives (p2c2-T2)/(2Tc2) = (2Tmoc2)/(2Tc2) I now have the required LHS of (1), This yields (p2c2-T2)/(2Tc2) = mo , NOT m !!!!!!! Where have i gone wrong !!!??