Question Number 209415 by RoseAli last updated on 09/Jul/24
Commented by Frix last updated on 09/Jul/24
$$\mathrm{This}\:\mathrm{is}\:\mathrm{just}\:\mathrm{a}\:\mathrm{term}. \\ $$$$\mathrm{No}\:\mathrm{question}\:\Rightarrow\:\mathrm{No}\:\mathrm{answer} \\ $$$$ \\ $$$$\mathrm{It}'\mathrm{s}\:\mathrm{like}\:\mathrm{these}: \\ $$$$\bullet\:\mathrm{5}{ab}^{\mathrm{2}} +\mathrm{7}{c}−\mathrm{3} \\ $$$$\bullet\:\mathrm{97}.\mathrm{3km}/\mathrm{hr} \\ $$$$\bullet\:\mathrm{A}\:\mathrm{bird}\:\mathrm{in}\:\mathrm{a}\:\mathrm{tree}. \\ $$
Answered by lepuissantcedricjunior last updated on 09/Jul/24
$$\boldsymbol{{x}}^{\mathrm{8}} +\mathrm{98}\boldsymbol{{x}}^{\mathrm{4}} +\mathrm{1}=\mathrm{0} \\ $$$$\boldsymbol{{posons}}\:\boldsymbol{{x}}^{\mathrm{4}} =\boldsymbol{{t}}=>\boldsymbol{{x}}^{\mathrm{8}} =\boldsymbol{{t}}^{\mathrm{2}} \\ $$$$\boldsymbol{{t}}^{\mathrm{2}} +\mathrm{98}\boldsymbol{{t}}+\mathrm{1}=\mathrm{0} \\ $$$$\boldsymbol{\Delta}=\mathrm{98}^{\mathrm{2}} −\mathrm{4}=\left(\mathrm{98}−\mathrm{4}\right)\left(\mathrm{98}+\mathrm{4}\right)=\mathrm{94}×\mathrm{102} \\ $$$$\:\:\:\:\:\boldsymbol{{t}}=\frac{−\mathrm{98}\pm\sqrt{\mathrm{94}×\mathrm{102}}}{\mathrm{2}} \\ $$$$\boldsymbol{{x}}^{\mathrm{4}} =\boldsymbol{{t}}=\frac{−\mathrm{98}+\sqrt{\mathrm{98}^{\mathrm{2}} \left(\mathrm{1}−\left(\frac{\mathrm{1}}{\mathrm{49}}\right)^{\mathrm{2}} \right)}}{\mathrm{2}} \\ $$$$\boldsymbol{{x}}=\sqrt[{\mathrm{4}}]{\mathrm{7}^{\mathrm{2}} \left(−\mathrm{1}+\sqrt{\mathrm{1}−\frac{\mathrm{1}}{\mathrm{49}^{\mathrm{2}} }}\right)=\sqrt{\mathrm{7}}\sqrt[{\mathrm{4}}]{\frac{\mathrm{1}}{\mathrm{7}}\sqrt{\mathrm{49}^{\mathrm{2}} −\mathrm{1}}}−\mathrm{1}} \\ $$
Commented by mr W last updated on 09/Jul/24
$${wrong}! \\ $$$$\Delta=\mathrm{98}^{\mathrm{2}} −\mathrm{4}=\left(\mathrm{98}−\mathrm{2}\right)\left(\mathrm{98}+\mathrm{2}\right)=\mathrm{96}×\mathrm{100}=\mathrm{9600} \\ $$