J²u a²u ax² at² + и, 0<x<π, t>0 u(0,t) = 0, u(π, t) = 0, t>0 x, 0<x<π/2 u(x, 0) TX, π/2≤x<T ди == = 0, 0<x<πT at=0 u(x, t) == 4 00 Σ π k=1 (-1)+1 (2k-1)² sin(2k -1)x cos√(2k - 1)²+1t.