Partial Differential Equation

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4. 4 In Example 4. 8, let the forcing term be f ( t , x ) = cos ( wt ) sin ( WK` ) , with w > O and KIT WK : = e Find the solution " ( 1 ,* ) given initial conditions 8 _ _ = O. Include both cases w * Wk and w = WK.Example 4. 8 Consider a string of length ( with propagation speed c = 1. Suppose the forcing term is given by f ( t , x ) = cos ( WE ) sin ( work ). ( 4. 28 )