Special Relativity, equation help needed

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punkstart
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Given that E2 = c2p2 + mo2c4-----------(1);
where p represents the relativistic momentum 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.



Homework Equations



E= T+moc2-------(2)

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 !??
 
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