partial differentiation equation
2ĆĀ· The scalar wave equation is given by Show by substitution (NOT separation of variables) that u = f(x-ct) + g(x + ct) is a general solution to this equation, where f and g are any possible functions whatsoever. (Hint: define y = x + ct, z = x-ct, and then use the chain rule for partial derivatives.) What do these two functions represent physically? (Hint: think about the direction of the wave.)
