Special solution of differential equation y '' = e ^ (2Y) y (0) = y '(0) = 0

Special solution of differential equation y '' = e ^ (2Y) y (0) = y '(0) = 0

Let P = y ', then y' '= dy' / DX = PDP / dy be substituted into the original equation to get p ^ 2 = e ^ (2Y) + C. from Y (0) = y '(0) = 0 to get C = - 1, so y = ln √ (P ^ 2 + 1) and y' = P = [P / (P ^ 2 + 1)] DP / DX, then x = arctanp + C = arctanp, that is y '= TaNx, then y = - ln | cosx | + C = - ln | cosx |