silemus.

47Partial derivative of exye^{xy}

Let f(x,y)=exy\displaystyle f(x, y) = e^{xy}. Find ∂f∂y\displaystyle \frac{\partial f}{\partial y} at (1,0)\displaystyle (1, 0).

Hold x fixed and differentiate e^(xy) with respect to y: ∂f/∂y = x·e^(xy). At (1,0) this is 1·e⁰ = 1.

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