Use the method of variation of parameters to solve the initial value problem x′=Ax+f(t),x(a)=x3​ using the following values. A=[416​−1−4​],f(t)=[46​],x(0)=[45​],eAt=[1+4t16t​−11−4t​] Use the method of variation of parameters to solve the initial value problem x′=Ax+f(t),x(a)=xa​ using the following values A=[39​−1−3​],f(t)=[68​],x(0)=[37​],eAt=[1+3t9t​−t1−3t​]