Calculate $\frac{\partial f}{\partial x}$, $\frac{\partial f}{\partial y}$, $\frac{\partial f}{\partial x}(1, -1)$, and $\frac{\partial f}{\partial y}(1, -1)$ when defined. (If an answer is undefined, enter UNDEFINED.)
$\qquad f(x, y) = e^{0.7xy}$
$\frac{\partial f}{\partial x} = 0.7y \cdot e^{0.7xy}$
$\frac{\partial f}{\partial y} = 0.7x \cdot e^{0.7xy}$
Round your answers to 4 decimal places.
$\frac{\partial f}{\partial x}(1, -1) = $
$\frac{\partial f}{\partial y}(1, -1) = $