Question Number 180351 by MikeH last updated on 10/Nov/22
$$\mathrm{solve}\:\mathrm{the}\:\mathrm{differential}\:\mathrm{equation}\:\:{y}''\:+\mathrm{2}\:{y}'\:+\:{y}\:=\:\mathrm{0} \\ $$$$\mathrm{using}\:\mathrm{power}\:\mathrm{series}\:\mathrm{method}\:\mathrm{that}\:\mathrm{is},\:\mathrm{assume} \\ $$$${y}\:=\:\underset{{n}=\mathrm{0}} {\overset{\infty} {\sum}}{c}_{{n}} {x}^{{n}} \:\mathrm{is}\:\mathrm{a}\:\mathrm{solution} \\ $$