Question Number 169800 by SANOGO last updated on 09/May/22
$${soit}\:{f}\left({x},{y}\right)={x}^{\mathrm{5}} {y}^{\mathrm{2}} \left({x}−{y}\right) \\ $$$${montrer}\:{q}\:{ue}\:{f}\:{est}\:{differentiable}\:{au}\:{point}\:{a}=\left(\mathrm{2}−\mathrm{1}\right) \\ $$$${applique}\:{en}\:{h}=\left(\mathrm{1},\mathrm{1}\right) \\ $$