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Variation of Parameters Solve the following differential equations by variation of parameters: 9) y" + y = secx 10) y" + 3y' + 2y = 1 1+ex 11) y" - 4y' + 4y = (24x2 + 2)e2x 12) y" + 2y'+y = e-Int9. y = q, cos x + c2 sin x + cos x In|cos x| + x sin x 10. y = Ge"* + Cze 2* + e-* In(1 + e*) +e-2x In(1 + ex) 11. y = Cje * + Caxex + (2x4 + x2 )e2x 12. y = get+ cate * + the-t Cint -9