Question Number 67337 by ajfour last updated on 25/Aug/19
$${m}\left({p}+\mathrm{1}\right)={a} \\ $$$$\frac{{q}\left({p}+\mathrm{1}\right)}{{r}+\mathrm{1}}={b}\:\:\&\:\:\frac{{p}\left({p}+\mathrm{1}\right)}{{q}+\mathrm{1}}={c} \\ $$$${and}\:\:\frac{{r}\left({p}+\mathrm{1}\right)}{{m}+\mathrm{1}}={d} \\ $$$${find}\:{either}\:{of}\:{p},{q},{r},{m}\:{in}\:{terms}\:{of} \\ $$$${a},{b},{c},{d}. \\ $$
Answered by mr W last updated on 25/Aug/19
$${m}=\frac{{a}}{{p}+\mathrm{1}} \\ $$$${q}=\frac{{p}\left({p}+\mathrm{1}\right)}{{c}}−\mathrm{1} \\ $$$${r}=\frac{{q}\left({p}+\mathrm{1}\right)}{{b}}−\mathrm{1}=\left[\frac{{p}\left({p}+\mathrm{1}\right)}{{c}}−\mathrm{1}\right]\frac{{p}+\mathrm{1}}{{b}}−\mathrm{1} \\ $$$${r}\left({p}+\mathrm{1}\right)={d}\left({m}+\mathrm{1}\right) \\ $$$$\left\{\left[\frac{{p}\left({p}+\mathrm{1}\right)}{{c}}−\mathrm{1}\right]\frac{{p}+\mathrm{1}}{{b}}−\mathrm{1}\right\}\left({p}+\mathrm{1}\right)=\left(\frac{{a}}{{p}+\mathrm{1}}+\mathrm{1}\right){d} \\ $$$${let}\:{p}+\mathrm{1}={t} \\ $$$$\left\{\left[\left({t}−\mathrm{1}\right){t}−{c}\right]{t}−{bc}\right\}{t}^{\mathrm{2}} =\left({a}+{t}\right){bcd} \\ $$$$\Rightarrow{t}^{\mathrm{5}} −{t}^{\mathrm{4}} −{ct}^{\mathrm{3}} −{bct}^{\mathrm{2}} −{bcdt}−{abcd}=\mathrm{0} \\ $$$$……??? \\ $$
Commented by ajfour last updated on 26/Aug/19
$${trying}\:{again}\:{to}\:{solve}\:{the}\:{general} \\ $$$${quintic}\:{i}\:{have}\:{stuck}\:{upon}\:{this}\:{Sir}! \\ $$