Bonjour,
[tex] A=\frac{a^2}{b^2}\times(\frac{4b}{b^5})^{-1/2} \\\\
A=\frac{a^2}{b^2}\times \frac{1}{(\frac{4b}{b^5})^{1/2}} \\\\
A=\frac{a^2}{b^2}\times \frac{1}{(\frac{4}{b^4})^{1/2}} \\\\
A=\frac{a^2}{b^2}\times \frac{1}{\sqrt{\frac{4}{b^4}}} \\\\
A=\frac{a^2}{b^2}\times \frac{1}{\frac{\sqrt{4}}{\sqrt{b^4}}} \\\\
A=\frac{a^2}{b^2}\times \frac{1}{\frac{2}{b^2}} \\\\
A=\frac{a^2}{b^2}\times \frac{b^2}{2} \\\\
\boxed{A=\frac{a^2}{2}}
[/tex]
Oui tu as raison :)
