Question Number 130884 by LYKA last updated on 30/Jan/21 | ||
$${let}\:{f}\left({x}.{y}\right)=\left[{x}^{\mathrm{2}} +{xy},{x}^{\mathrm{2}} −{y}^{\mathrm{2}} \right]\: \\ $$$$ \\ $$$${prove}\:{from}\:{defination}\:{of}\: \\ $$$${derivative}\:{that}\:: \\ $$$${Df}_{\left({x},{y}\right)} \left(\mathrm{1},\mathrm{2}\right)=\left[\mathrm{4}\boldsymbol{{x}}+\boldsymbol{{y}},−\mathrm{2}{x}+\mathrm{4}{y}\right] \\ $$$$ \\ $$ | ||
Commented by LYKA last updated on 30/Jan/21 | ||
$${okay}\:{sir} \\ $$ | ||