Question Number 121957 by mlj5 last updated on 13/Nov/20
$${resoudre}\:{equation}\mid−\mathrm{2}{x}−\sqrt{\mathrm{3}/}\mathrm{4}\mid=\mathrm{5}−\mathrm{2}\sqrt{\mathrm{7}} \\ $$
Commented by MJS_new last updated on 13/Nov/20
![what does [...] mean? usually it′s the greatest integer function, in this case the equation has no solution: [...]∈Z but 5−2(√7)∉Z](Q121971.png)
$$\mathrm{what}\:\mathrm{does}\:\left[...\right]\:\mathrm{mean}?\:\mathrm{usually}\:\mathrm{it}'\mathrm{s}\:\mathrm{the}\:\mathrm{greatest} \\ $$$$\mathrm{integer}\:\mathrm{function},\:\mathrm{in}\:\mathrm{this}\:\mathrm{case}\:\mathrm{the}\:\mathrm{equation} \\ $$$$\mathrm{has}\:\mathrm{no}\:\mathrm{solution}:\:\left[...\right]\in\mathbb{Z}\:\mathrm{but}\:\mathrm{5}−\mathrm{2}\sqrt{\mathrm{7}}\notin\mathbb{Z} \\ $$
Commented by mlj5 last updated on 13/Nov/20
$${please}\:{help}\:\mid−\mathrm{2}{x}−\sqrt{\mathrm{3}/}\mathrm{4}\mid=\mathrm{5}−\mathrm{2}\sqrt{\mathrm{7}} \\ $$
Commented by MJS_new last updated on 13/Nov/20
$$\mathrm{if}\:\mathrm{it}'\mathrm{s}\:\mathrm{absolute}\:\left(−\mathrm{2}{x}−\frac{\sqrt{\mathrm{3}}}{\mathrm{4}}\right)\:\mathrm{we}\:\mathrm{have}\:\mathrm{no} \\ $$$$\mathrm{solution}\:\mathrm{again}\:\mathrm{because}\:\mathrm{abs}\:\left({X}\right)\:\geqslant\mathrm{0}\:\mathrm{but} \\ $$$$\mathrm{5}−\mathrm{2}\sqrt{\mathrm{7}}<\mathrm{0} \\ $$
Commented by mlj5 last updated on 13/Nov/20
$${thanks} \\ $$