Question Number 44892 by Tawa1 last updated on 06/Oct/18
$$\mathrm{Find}\:\mathrm{the}\:\mathrm{formular}\:\mathrm{for}\:\mathrm{the}\:\mathrm{sum}\:\mathrm{of}\:\mathrm{the}\:\mathrm{first}\:\mathrm{kth}\:\mathrm{power}\:\mathrm{of}\:\mathrm{natural}\:\mathrm{number} \\ $$
Commented by tanmay.chaudhury50@gmail.com last updated on 06/Oct/18
$${do}\:{the}\:{question}\:{mean} \\ $$$${S}_{{k}} =\mathrm{1}^{{k}} +\mathrm{2}^{{k}} +\mathrm{3}^{{k}} +…+{n}^{{k}} \: \\ $$$${pls}\:{reply} \\ $$
Commented by Tawa1 last updated on 06/Oct/18
$$\mathrm{Yes}\:\mathrm{sir}.\:\mathrm{exactly},\:\:\mathrm{Thanks}\:\mathrm{for}\:\mathrm{your}\:\mathrm{help}\:\mathrm{sir}.\:\:\mathrm{God}\:\mathrm{bless}\:\mathrm{you} \\ $$
Answered by tanmay.chaudhury50@gmail.com last updated on 06/Oct/18
Commented by tanmay.chaudhury50@gmail.com last updated on 06/Oct/18
Commented by tanmay.chaudhury50@gmail.com last updated on 06/Oct/18
Commented by tanmay.chaudhury50@gmail.com last updated on 06/Oct/18
Commented by Tawa1 last updated on 06/Oct/18
$$\mathrm{God}\:\mathrm{bless}\:\mathrm{you}\:\mathrm{sir}.\:\mathrm{i}\:\mathrm{appreciate} \\ $$
Commented by Tawa1 last updated on 06/Oct/18
$$\mathrm{Sir},\:\mathrm{am}\:\mathrm{trying}\:\mathrm{to}\:\mathrm{understand}\:\mathrm{the}\:\mathrm{theorem}\:\mathrm{but}\:\mathrm{am}\:\mathrm{confused}. \\ $$$$\mathrm{Can}\:\mathrm{you}\:\mathrm{help}\:\mathrm{me}\:\mathrm{to}\:\mathrm{use}\:\mathrm{the}\:\mathrm{theorem}\:\mathrm{to}\:\mathrm{find}\:\mathrm{the}\:\mathrm{sum}\:\mathrm{of}\:\mathrm{n}\:\mathrm{terms} \\ $$$$\:\:\mathrm{1}^{\mathrm{5}} \:+\:\mathrm{2}^{\mathrm{5}} \:+\:\mathrm{3}^{\mathrm{5}} \:+\:\mathrm{4}^{\mathrm{5}} \:+\:…\:\:\:\:\:\:\:\mathrm{or}\:\mathrm{any}\:\mathrm{example}. \\ $$$$\mathrm{Please},\:\mathrm{i}\:\mathrm{will}\:\mathrm{read}\:\mathrm{through}\:\mathrm{your}\:\mathrm{example}\:\mathrm{and}\:\mathrm{understand}.\:\:\mathrm{God}\:\mathrm{bless}\:\mathrm{you} \\ $$$$\mathrm{sir}.\:\mathrm{And}\:\mathrm{thanks}\:\mathrm{for}\:\mathrm{everytime} \\ $$
Commented by tanmay.chaudhury50@gmail.com last updated on 06/Oct/18
$${S}_{{r}} ={r}\int{S}_{{r}−\mathrm{1}} {dn}+{nB}_{{r}} \\ $$$${to}\:{find}\:{S}_{\mathrm{5}} \:\:{we}\:{need}\:{the}\:{value}\:{of}\:{S}_{\mathrm{4}} \\ $$$${now}\:{S}_{\mathrm{3}} =\mathrm{1}^{\mathrm{3}} +\mathrm{2}^{\mathrm{3}} +\mathrm{3}^{\mathrm{3}} +..+{n}^{\mathrm{3}} \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:=\left\{\frac{{n}\left({n}+\mathrm{1}\right)}{\mathrm{2}}\right\}^{\mathrm{2}} =\frac{{n}^{\mathrm{2}} \left({n}^{\mathrm{2}} +\mathrm{2}{n}+\mathrm{1}\right)}{\mathrm{4}}=\frac{{n}^{\mathrm{4}} +\mathrm{2}{n}^{\mathrm{3}} +{n}^{\mathrm{2}} }{\mathrm{4}} \\ $$$${S}_{\mathrm{4}} =\mathrm{4}\int\frac{{n}^{\mathrm{4}} +\mathrm{2}{n}^{\mathrm{3}} +{n}^{\mathrm{2}} }{\mathrm{4}}{dn}+{nB}_{\mathrm{4}} \\ $$$$\:\:=\frac{{n}^{\mathrm{5}} }{\mathrm{5}}+\frac{\mathrm{2}{n}^{\mathrm{4}} }{\mathrm{4}}+\frac{{n}^{\mathrm{3}} }{\mathrm{3}}+{n}×\frac{−\mathrm{1}}{\mathrm{30}} \\ $$$$=\frac{{n}^{\mathrm{5}} }{\mathrm{5}}+\frac{{n}^{\mathrm{4}} }{\mathrm{2}\:}+\frac{{n}^{\mathrm{3}} }{\mathrm{3}}−\frac{{n}}{\mathrm{30}} \\ $$$${S}_{\mathrm{5}} =\mathrm{5}\int{S}_{\mathrm{4}} {dn}+{nB}_{\mathrm{5}} \\ $$$${S}_{\mathrm{5}} =\mathrm{5}\int\frac{{n}^{\mathrm{5}} }{\mathrm{5}}+\frac{{n}^{\mathrm{4}} }{\mathrm{2}}+\frac{{n}^{\mathrm{3}} }{\mathrm{3}}−\frac{{n}}{\mathrm{30}}{dn}+{nB}_{\mathrm{5}} \\ $$$${S}_{\mathrm{5}} =\mathrm{5}\left\{\frac{{n}^{\mathrm{6}} }{\mathrm{30}}+\frac{{n}^{\mathrm{5}} }{\mathrm{10}}+\frac{{n}^{\mathrm{4}} }{\mathrm{12}}−\frac{{n}^{\mathrm{2}} }{\mathrm{60}}\right\}+{nB}_{\mathrm{5}} \\ $$$${S}_{\mathrm{5}} =\frac{{n}^{\mathrm{6}} }{\mathrm{6}}+\frac{{n}^{\mathrm{5}} }{\mathrm{2}}+\frac{\mathrm{5}{n}^{\mathrm{4}} }{\mathrm{12}}−\frac{{n}^{\mathrm{2}} }{\mathrm{12}}+{nB}_{\mathrm{5}} \:\: \\ $$$${value}\:{of}\:{B}_{\mathrm{5}} =\mathrm{0}\:{so} \\ $$$$\mathrm{1}^{\mathrm{5}} +\mathrm{2}^{\mathrm{5}} +\mathrm{3}^{\mathrm{5}} +…+{n}^{\mathrm{5}} =\frac{{n}^{\mathrm{6}} }{\mathrm{6}}+\frac{{n}^{\mathrm{5}} }{\mathrm{2}}+\frac{\mathrm{5}{n}^{\mathrm{4}} }{\mathrm{12}}−\frac{{n}^{\mathrm{2}} }{\mathrm{12}} \\ $$$$ \\ $$
Commented by tanmay.chaudhury50@gmail.com last updated on 06/Oct/18
Commented by Tawa1 last updated on 06/Oct/18
$$\mathrm{Wow},\:\mathrm{God}\:\mathrm{bless}\:\mathrm{you}\:\mathrm{sir}.\:\mathrm{Thanks}\:\mathrm{for}\:\mathrm{your}\:\mathrm{time} \\ $$
Commented by Tawa1 last updated on 06/Oct/18
$$\mathrm{I}\:\mathrm{really}\:\mathrm{understand}\:\mathrm{now}.\:\mathrm{God}\:\mathrm{bless}\:\mathrm{you}\:\mathrm{sir} \\ $$