In the equation where y" + 4y = 0, A. Show a solution for all the values of the arbitrary constants A and Z in y(x)= A sin wx + Z cos wx B. What should be the interval of validity in the solution?

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Extracted text: In the equation where y" + 4y = 0, A. Show a solution for all the values of the arbitrary constants A and Z in y(x)= A sin wx + Z cos wx B. What should be the interval of validity in the solution?