Question Number 211255 by ajfour last updated on 02/Sep/24
$$\sqrt{{a}+\sqrt{{b}−{x}}+\sqrt{{b}−\sqrt{{a}+{x}}}}=\mathrm{2}{x} \\ $$$${solve}\:{for}\:{x}.\:\:\:\: \\ $$
Commented by Ghisom last updated on 03/Sep/24
$$\sqrt{{a}+\sqrt{{b}−{x}}+\sqrt{{b}−\sqrt{{a}+{x}}}}=\mathrm{2}{x} \\ $$$${x}=\left({b}−\left(\mathrm{4}{x}^{\mathrm{2}} −\sqrt{{b}−{x}}−{a}\right)^{\mathrm{2}} \right)^{\mathrm{2}} −{a} \\ $$$$\mathrm{it}'\mathrm{s}\:\mathrm{already}\:\mathrm{of}\:\mathrm{8}^{\mathrm{th}} \:\mathrm{degree}\:\mathrm{and}\:\mathrm{we}\:\mathrm{still}\:\mathrm{have} \\ $$$$\sqrt{{b}−{x}}\:\Rightarrow\:\mathrm{it}'\mathrm{s}\:\mathrm{of}\:\mathrm{16}^{\mathrm{th}} \:\mathrm{degree}.\:\mathrm{we}\:\mathrm{can}'\mathrm{t}\:\mathrm{solve} \\ $$$$\mathrm{for}\:{x}\:\mathrm{nor}\:\mathrm{for}\:{a}.\:\mathrm{but}\:\mathrm{we}\:\mathrm{can}\:\mathrm{for}\:{b}: \\ $$$${b}=\frac{\mathrm{256}{x}^{\mathrm{8}} −\mathrm{256}{ax}^{\mathrm{6}} +\mathrm{32}{x}^{\mathrm{5}} +\mathrm{96}{a}^{\mathrm{2}} {x}^{\mathrm{4}} −\mathrm{16}{ax}^{\mathrm{3}} −\left(\mathrm{16}{a}^{\mathrm{3}} −\mathrm{1}\right){x}^{\mathrm{2}} +\left(\mathrm{2}{a}^{\mathrm{2}} +\mathrm{1}\right){x}+{a}\left({a}^{\mathrm{3}} +\mathrm{1}\right)}{\mathrm{4}\left(\mathrm{4}{x}^{\mathrm{2}} −{a}\right)^{\mathrm{2}} }+\frac{\left(\mathrm{16}{x}^{\mathrm{4}} −\mathrm{8}{ax}^{\mathrm{2}} −{x}+{a}^{\mathrm{2}} \right)\sqrt{{a}+{x}}}{\mathrm{2}\left(\mathrm{4}{x}^{\mathrm{2}} −{a}\right)^{\mathrm{2}} } \\ $$$$\left[\mathrm{might}\:\mathrm{not}\:\mathrm{always}\:\mathrm{be}\:\mathrm{true}\:\mathrm{because}\:\mathrm{of}\:\mathrm{3}\right. \\ $$$$\left.\mathrm{times}\:\mathrm{squaring}\right] \\ $$
Commented by ajfour last updated on 06/Sep/24
$$\sqrt{{a}+\sqrt{{b}−{x}}}+\sqrt{{b}−\sqrt{{a}+{x}}}=\mathrm{2}{x} \\ $$$${i}\:{think}\:{i}\:{was}\:{interested}\:{in}\:{this}!\:{rather} \\ $$
Commented by ajfour last updated on 06/Sep/24
$${let}\:\:{a}+{x}={p}^{\mathrm{2}} \:\:,\:\:{b}−{x}={q}^{\mathrm{2}} \\ $$$${p}^{\mathrm{2}} +{q}^{\mathrm{2}} ={a}+{b} \\ $$$$\mathrm{2}{x}=\left({p}^{\mathrm{2}} −{q}^{\mathrm{2}} \right)−\left({a}−{b}\right) \\ $$$$\sqrt{{a}+{q}}+\sqrt{{b}−{p}}={p}^{\mathrm{2}} −{q}^{\mathrm{2}} −\left({a}−{b}\right) \\ $$$${squaring} \\ $$$${a}+{q}=\left\{\mathrm{2}\left({p}^{\mathrm{2}} −{a}\right)−\sqrt{{b}−{p}}\right\}^{\mathrm{2}} \\ $$$${a}+{b}−{p}^{\mathrm{2}} =\left[\left\{\mathrm{2}\left({p}^{\mathrm{2}} −{a}\right)−\sqrt{{b}−{p}}\right\}^{\mathrm{2}} −{a}\right]^{\mathrm{2}} \\ $$$$….. \\ $$
Answered by a.lgnaoui last updated on 03/Sep/24
$$\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:=\:\sqrt{\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}}\:+\sqrt{\boldsymbol{\mathrm{b}}−\sqrt{\boldsymbol{\mathrm{a}}+\boldsymbol{\mathrm{x}}}} \\ $$$$\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)−\sqrt{\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}}\:=\sqrt{\boldsymbol{\mathrm{b}}−\sqrt{\boldsymbol{\mathrm{a}}+\boldsymbol{\mathrm{x}}}} \\ $$$$\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{2}} −\boldsymbol{\mathrm{x}}−\mathrm{2}\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)\sqrt{\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}}\:= \\ $$$$−\sqrt{\boldsymbol{\mathrm{a}}+\boldsymbol{\mathrm{x}}} \\ $$$$ \\ $$$$\left(\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{2}} −\boldsymbol{\mathrm{x}}=\mathrm{2}\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)\sqrt{\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}}\:−\sqrt{\boldsymbol{\mathrm{a}}+\boldsymbol{\mathrm{x}}}\right. \\ $$$$ \\ $$$$\left.\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{2}} +\sqrt{\boldsymbol{\mathrm{a}}+\boldsymbol{\mathrm{x}}}\:=\mathrm{2}\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)\sqrt{\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}} \\ $$$$\frac{\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}}{\mathrm{2}}+\frac{\sqrt{\boldsymbol{\mathrm{a}}+\boldsymbol{\mathrm{x}}}}{\mathrm{2}\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)}=\sqrt{\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}} \\ $$$$\frac{\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{2}} }{\mathrm{4}}+\frac{\boldsymbol{\mathrm{a}}+\boldsymbol{\mathrm{x}}}{\mathrm{4}\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{2}} }+\frac{\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)\sqrt{\boldsymbol{\mathrm{a}}+\boldsymbol{\mathrm{x}}}}{\mathrm{2}}=\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}} \\ $$$$ \\ $$$$\sqrt{\boldsymbol{\mathrm{a}}+\boldsymbol{\mathrm{x}}}\:=\frac{\mathrm{2}}{\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)}\left[\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}−\frac{\boldsymbol{\mathrm{a}}+\boldsymbol{\mathrm{x}}}{\mathrm{4}\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{2}} }−\frac{\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{2}} }{\mathrm{4}}\right] \\ $$$$ \\ $$$$\sqrt{\mathrm{a}+\boldsymbol{\mathrm{x}}}\:=\frac{\mathrm{2}}{\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}}\left[\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}−\left(\frac{\left[\left(\boldsymbol{\mathrm{a}}+\boldsymbol{\mathrm{x}}\right)+\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{4}} \right.}{\mathrm{4}\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{2}} }\right)\right. \\ $$$$ \\ $$$$\:\:\:\:\:\:\:=\left[\frac{\mathrm{2}\left(\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}\right)\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)−\left(\boldsymbol{\mathrm{a}}+\boldsymbol{\mathrm{x}}\right)−\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{4}} }{\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{2}} }\right] \\ $$$$=\frac{\left[\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)\left[\left(\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}\right)−\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{3}} \right]\right.}{\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{2}} } \\ $$$$ \\ $$$$\boldsymbol{\mathrm{a}}+\boldsymbol{\mathrm{x}}=\frac{\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{2}} \left(\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}−\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{3}} \right)^{\mathrm{2}} }{\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{4}} } \\ $$$$ \\ $$$$ \\ $$$$\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\mathrm{a}\right)^{\mathrm{4}} \left(\mathrm{a}+\boldsymbol{\mathrm{x}}\right)= \\ $$$$\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{2}} \left[\left(\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}\right)^{\mathrm{2}} +\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{6}} −\mathrm{2}\left(\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}\right)\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{3}} \right] \\ $$$$ \\ $$$$ \\ $$$$\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{2}} \left(\boldsymbol{\mathrm{a}}+\boldsymbol{\mathrm{x}}\right)\:\:= \\ $$$$\left.\:\:\left(\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}\right)^{\mathrm{2}} +\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{6}} −\mathrm{2}\left(\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}\right)\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{3}} \right] \\ $$$$ \\ $$$$\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{2}} \left(\boldsymbol{\mathrm{a}}+\boldsymbol{\mathrm{x}}\right)−\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{6}} +\mathrm{2}\left(\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}\right)\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{3}} \\ $$$$=\left(\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}\right)^{\mathrm{2}} \\ $$$$ \\ $$$$\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{2}} \left[\boldsymbol{\mathrm{a}}+\boldsymbol{\mathrm{x}}−\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{4}} +\mathrm{2}\left(\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}\right)\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)\right] \\ $$$$ \\ $$$$=\left(\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}\right)^{\mathrm{2}} \\ $$$$\left[\boldsymbol{\mathrm{a}}+\boldsymbol{\mathrm{x}}+\mathrm{8}\boldsymbol{\mathrm{bx}}^{\mathrm{2}} −\mathrm{2}\boldsymbol{\mathrm{ab}}−\mathrm{8}\boldsymbol{\mathrm{x}}^{\mathrm{3}} +\mathrm{2}\boldsymbol{\mathrm{ax}}\right. \\ $$$$−\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{4}} =\left(\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}\right)^{\mathrm{2}} \\ $$$$ \\ $$$$\left(\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}\right)^{\mathrm{2}} +\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\mathrm{a}\right)^{\mathrm{4}} = \\ $$$$ \\ $$$$\left[\left(\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}+\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{2}} \right]^{\mathrm{2}} −\mathrm{2}\left(\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}\right)\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{2}} \right. \\ $$$$ \\ $$$$ \\ $$$$\mathrm{soit} \\ $$$$\:\:−\mathrm{8}\boldsymbol{\mathrm{x}}^{\mathrm{3}} +\mathrm{8}\boldsymbol{\mathrm{bx}}^{\mathrm{2}} +\left(\mathrm{2}\boldsymbol{\mathrm{a}}+\mathrm{1}\right)\boldsymbol{\mathrm{x}}+\boldsymbol{\mathrm{a}}\left(\mathrm{1}−\mathrm{2}\boldsymbol{\mathrm{b}}\right)= \\ $$$$\boldsymbol{\mathrm{b}}^{\mathrm{2}} +\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\mathrm{2}\boldsymbol{\mathrm{bx}}+\left(\mathrm{16}\boldsymbol{\mathrm{x}}^{\mathrm{4}} +\boldsymbol{\mathrm{a}}^{\mathrm{2}} −\mathrm{8}\boldsymbol{\mathrm{ax}}^{\mathrm{2}} \right)^{\mathrm{2}} \\ $$$$+\mathrm{2}\left(\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}\right)\left(\mathrm{4}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\right)^{\mathrm{2}} \\ $$$$ \\ $$$$=\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\mathrm{2}\boldsymbol{\mathrm{bx}}\:+\boldsymbol{\mathrm{b}}^{\mathrm{2}} +\left[\mathrm{8}\boldsymbol{\mathrm{x}}^{\mathrm{2}} \left(\boldsymbol{\mathrm{a}}+\mathrm{2}\boldsymbol{\mathrm{x}}^{\mathrm{2}} \right)+\boldsymbol{\mathrm{a}}^{\mathrm{2}} \right] \\ $$$$\:\:\:+\mathrm{64}\boldsymbol{\mathrm{x}}^{\mathrm{4}} \left(\boldsymbol{\mathrm{a}}+\mathrm{2}\boldsymbol{\mathrm{x}}^{\mathrm{2}} \right)^{\mathrm{2}} +\boldsymbol{\mathrm{a}}^{\mathrm{4}} +\mathrm{16}\boldsymbol{\mathrm{a}}^{\mathrm{2}} \left(\boldsymbol{\mathrm{a}}+\mathrm{2}\boldsymbol{\mathrm{x}}^{\mathrm{2}} \right) \\ $$$$\left.\:\:\:+\mathrm{2}\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{x}}\right)\left(\mathrm{16}\boldsymbol{\mathrm{x}}^{\mathrm{4}} +\boldsymbol{\mathrm{a}}^{\mathrm{2}} −\mathrm{8}\boldsymbol{\mathrm{ax}}^{\mathrm{2}} \right) \\ $$$$\Rightarrow \\ $$$$\left(\mathrm{256}+\boldsymbol{\mathrm{a}}\right)\boldsymbol{\mathrm{x}}^{\mathrm{6}} −\mathrm{16}\boldsymbol{\mathrm{x}}^{\mathrm{5}} +\left(\mathrm{64}\boldsymbol{\mathrm{a}}^{\mathrm{2}} +\mathrm{32}\boldsymbol{\mathrm{b}}+\mathrm{8}\boldsymbol{\mathrm{a}}\right)\boldsymbol{\mathrm{x}}^{\mathrm{4}} +\mathrm{8}\left(\boldsymbol{\mathrm{a}}+\mathrm{1}\right)\boldsymbol{\mathrm{x}}^{\mathrm{3}} \\ $$$$\left(\mathrm{32}\boldsymbol{\mathrm{a}}^{\mathrm{2}} −\mathrm{16}\boldsymbol{\mathrm{ab}}−\mathrm{8}\right)\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\left(\boldsymbol{\mathrm{a}}^{\mathrm{2}} +\mathrm{2}\boldsymbol{\mathrm{a}}+\mathrm{1}\right)\boldsymbol{\mathrm{x}}+\mathrm{16}\boldsymbol{\mathrm{a}}^{\mathrm{3}} +\mathrm{a}^{\mathrm{4}} −\boldsymbol{\mathrm{a}}\left(\mathrm{1}−\mathrm{2}\boldsymbol{\mathrm{b}}\right)=\mathrm{0} \\ $$$$ \\ $$$$ \\ $$$$\mathrm{256}\left(\mathrm{1}+\boldsymbol{\mathrm{a}}\right)\boldsymbol{\mathrm{x}}^{\mathrm{6}} −\mathrm{16}\boldsymbol{\mathrm{x}}^{\mathrm{5}} +\mathrm{8}\left(\mathrm{8a}^{\mathrm{2}} +\mathrm{4b}+\mathrm{a}\right)\boldsymbol{\mathrm{x}}^{\mathrm{4}} \\ $$$$+\mathrm{8}\left(\boldsymbol{\mathrm{a}}+\mathrm{1}\right)\boldsymbol{\mathrm{x}}^{\mathrm{3}} +\mathrm{8}\left(\mathrm{4}\boldsymbol{\mathrm{a}}^{\mathrm{2}} −\mathrm{2}\boldsymbol{\mathrm{ab}}−\mathrm{1}\right)\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\left(\boldsymbol{\mathrm{a}}+\mathrm{1}\right)^{\mathrm{2}} \boldsymbol{\mathrm{x}} \\ $$$$+\boldsymbol{\mathrm{a}}^{\mathrm{4}} +\mathrm{16}\boldsymbol{\mathrm{a}}^{\mathrm{3}} −\boldsymbol{\mathrm{a}}+\mathrm{2}\boldsymbol{\mathrm{ab}}=\mathrm{0} \\ $$$$ \\ $$$$ \\ $$$$\left(\mathrm{256}\boldsymbol{\mathrm{x}}^{\mathrm{6}} −\mathrm{16}\boldsymbol{\mathrm{x}}^{\mathrm{5}} +\mathrm{8}\boldsymbol{\mathrm{x}}^{\mathrm{3}} −\mathrm{8}\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{x}}\right)+ \\ $$$$\mathrm{256}\boldsymbol{\mathrm{ax}}^{\mathrm{6}} +\mathrm{8}\left(\mathrm{8}\boldsymbol{\mathrm{a}}^{\mathrm{2}} +\mathrm{4}\boldsymbol{\mathrm{b}}+\boldsymbol{\mathrm{a}}\right)\boldsymbol{\mathrm{x}}^{\mathrm{4}} +\mathrm{8}\boldsymbol{\mathrm{ax}}^{\mathrm{3}} \\ $$$$+\mathrm{16}\left(\mathrm{2}\boldsymbol{\mathrm{a}}^{\mathrm{2}} −\boldsymbol{\mathrm{ab}}\right)\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\left(\boldsymbol{\mathrm{a}}^{\mathrm{2}} +\mathrm{2}\boldsymbol{\mathrm{a}}\right)\boldsymbol{\mathrm{x}}+ \\ $$$$\boldsymbol{\mathrm{a}}^{\mathrm{4}} +\mathrm{16}\boldsymbol{\mathrm{a}}^{\mathrm{3}} −\boldsymbol{\mathrm{a}}+\mathrm{2}\boldsymbol{\mathrm{ab}}=\mathrm{0} \\ $$$$ \\ $$$$\begin{cases}{\mathrm{256}\boldsymbol{\mathrm{x}}^{\mathrm{5}} −\mathrm{16}\boldsymbol{\mathrm{x}}^{\mathrm{4}} +\mathrm{8}\boldsymbol{\mathrm{x}}^{\mathrm{2}} +\mathrm{8}\boldsymbol{\mathrm{x}}−\mathrm{1}=\mathrm{0}}\\{\mathrm{8}\left[\mathrm{32}\boldsymbol{\mathrm{ax}}^{\mathrm{6}} +\left(\mathrm{8}\boldsymbol{\mathrm{a}}^{\mathrm{2}} +\mathrm{4}\boldsymbol{\mathrm{b}}+\boldsymbol{\mathrm{a}}\right)\boldsymbol{\mathrm{x}}^{\mathrm{4}} +\boldsymbol{\mathrm{ax}}^{\mathrm{3}} +\right.}\end{cases} \\ $$$$\left.\boldsymbol{\mathrm{a}}\left(\mathrm{4}\boldsymbol{\mathrm{a}}−\boldsymbol{\mathrm{b}}\right)\boldsymbol{\mathrm{x}}^{\mathrm{2}} −\boldsymbol{\mathrm{a}}\left(\boldsymbol{\mathrm{a}}+\mathrm{2}\right)\boldsymbol{\mathrm{x}}\right]+ \\ $$$$\boldsymbol{\mathrm{a}}\left(\boldsymbol{\mathrm{a}}^{\mathrm{3}} +\mathrm{26}\boldsymbol{\mathrm{a}}^{\mathrm{2}} −\mathrm{1}+\mathrm{2}\boldsymbol{\mathrm{b}}\right)=\mathrm{0} \\ $$$$ \\ $$$$\:\:\begin{cases}{\boldsymbol{\mathrm{x}}=\mathrm{0},\mathrm{112166986}…\:\:\mathrm{and}\:\mathrm{imsg}\left(\mathrm{x}\right)\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\left(\mathrm{1}\right)}\\{\mathrm{8}\boldsymbol{\mathrm{ax}}\left(\mathrm{32}\boldsymbol{\mathrm{x}}^{\mathrm{5}} +\boldsymbol{\mathrm{x}}^{\mathrm{2}} +\left(\mathrm{4}\boldsymbol{\mathrm{a}}−\boldsymbol{\mathrm{b}}\right)\boldsymbol{\mathrm{x}}−\left(\boldsymbol{\mathrm{a}}+\mathrm{2}\right)=\mathrm{0}\left(\mathrm{2}\right)\right.}\end{cases} \\ $$$$\bullet\mathrm{3}\:\:\:\mathrm{a}^{\mathrm{3}} +\mathrm{16a}^{\mathrm{2}} +\mathrm{2b}−\mathrm{1}=\mathrm{0} \\ $$$$ \\ $$$$ \\ $$$$\mathrm{1}\bullet\:\:\:\:\mathrm{x}= \\ $$$$\mathrm{2}\boldsymbol{\mathrm{et}}\:\mathrm{3}\bullet\:\:\:\:\begin{cases}{\mathrm{32}\boldsymbol{\mathrm{x}}^{\mathrm{5}} +\boldsymbol{\mathrm{x}}^{\mathrm{2}} +\left(\mathrm{4}\boldsymbol{\mathrm{a}}−\boldsymbol{\mathrm{b}}\right)\boldsymbol{\mathrm{x}}=\boldsymbol{\mathrm{a}}+\mathrm{2}}\\{\:\:\:\boldsymbol{\mathrm{a}}^{\mathrm{3}} +\mathrm{16}\boldsymbol{\mathrm{a}}^{\mathrm{2}} +\mathrm{2}\boldsymbol{\mathrm{b}}−\mathrm{1}\:\:\:\:\:=\mathrm{0}}\end{cases} \\ $$$$ \\ $$$$\mathrm{a}^{\mathrm{2}} \left(\mathrm{a}+\mathrm{16}\right)=\mathrm{1}−\mathrm{2b} \\ $$$$\:\:\:\boldsymbol{\mathrm{b}}=\frac{\mathrm{1}−\boldsymbol{\mathrm{a}}^{\mathrm{2}} \left(\boldsymbol{\mathrm{a}}+\mathrm{16}\right)}{\mathrm{2}} \\ $$$$\mathrm{4}\boldsymbol{\mathrm{a}}−\boldsymbol{\mathrm{b}}=\frac{\boldsymbol{\mathrm{a}}^{\mathrm{2}} \left(\boldsymbol{\mathrm{a}}+\mathrm{16}\right)+\mathrm{8}\boldsymbol{\mathrm{a}}−\mathrm{1}}{\mathrm{2}} \\ $$$$\left(\mathrm{2}\right)\Rightarrow\:\:\mathrm{32x}^{\mathrm{5}} +\mathrm{x}^{\mathrm{2}} +\frac{\boldsymbol{\mathrm{a}}^{\mathrm{2}} \left(\mathrm{a}+\mathrm{16}\right)+\mathrm{8}\boldsymbol{\mathrm{a}}−\mathrm{1}}{\mathrm{2}}\boldsymbol{\mathrm{x}}=\boldsymbol{\mathrm{a}}+\mathrm{2} \\ $$$$\boldsymbol{\mathrm{we}}\:\boldsymbol{\mathrm{change}}\:\boldsymbol{\mathrm{x}}\:\boldsymbol{\mathrm{by}}\:\:\boldsymbol{\mathrm{x}}_{\mathrm{0}} =\mathrm{0},\mathrm{1121167}. \\ $$$$\Rightarrow\mathrm{we}\:\mathrm{bave}\:\:\mathrm{equation}\:\:\:\mathrm{with}\:\boldsymbol{\mathrm{a}}\:\boldsymbol{\mathrm{as}}\:\boldsymbol{\mathrm{unconnu}} \\ $$$$\boldsymbol{\mathrm{then}}\:\:\boldsymbol{\mathrm{we}}\:\boldsymbol{\mathrm{found}}\:\:\:\boldsymbol{\mathrm{a}}\:\:\:\boldsymbol{\mathrm{and}}\:\boldsymbol{\mathrm{b}}\: \\ $$$$\left(\mathrm{exept}\:\mathrm{Ereur}\:\mathrm{in}\:\mathrm{the}\:\mathrm{Calcul}\right) \\ $$
Commented by Ghisom last updated on 03/Sep/24
$$\mathrm{some}\:\mathrm{steps}\:\mathrm{are}\:\mathrm{not}\:\mathrm{clear}\:\mathrm{and}\:\mathrm{I}\:\mathrm{don}'\mathrm{t}\:\mathrm{think} \\ $$$$\mathrm{your}\:\mathrm{result}\:\mathrm{holds}. \\ $$