Explain the answers please

1, 0 1 1 - cos(2n7)] sin(nux) (e) None of these nTT nTT n=1 n=1 15. The solution of the heat equation Uzz = Ut, 0 0, which satisfies the boundary conditions ux(0, t) = Ux(1, t) = 0 and the initial condition u(x, 0) = x, is u(x, t) = DO (a) + 2[1 - (-1)"] cos(nix)en2*2t 1 - (-1)n n2 7 2 ( b ) 1 + cos(nTx)en2x2t n= n 27 2 n=1 (c) 2[(-1)" - 1] + cos(nux)en2*2t n 2 TT 2 (d) E 2(-1)" sin(nux)e-2*2t n=1 n=1 (e) None of these