  For the Tornheim double zeta function T(s1,s2,s3) of complex variables,we
obtain its functional equations,which are new.Using the calculus of r-th order
derivative of zeta(s,alpha) as a function of alpha(developed in author[7])as
the tool,we obtain with ease an expression for T(s,s,s) for any complex s;and
evaluate T(n,n,n) for any integer n>=1;and also evaluate T(n1,0,n2)for integers
n1,n2>1 with n1+n2 odd.We obtain for Tornheim zeta function,the counterparts of
Euler's formula for zeta(2n)and its analogue for zeta(2n+1),where Zeta(s) is
Riemann zeta function.
