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Question
Find the partial dervatives of the following functions at indicated points.
f(x, y) = 3x2 – 2xy + y2 + 5x + 2, (2, – 5)
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Solution
f(x, y) = 3x2 – 2xy + y2 + 5x + 2
`(delf)/(delx)` = 6x – 2y + 5
`(delf)/(dely)` = – 2x + 2y
At (2, – 5)
⇒ `(delf)/(delx)` = 6(2) – 2(– 5) + 5
= 27
`(delf)/(delx)` = – 2(2) + 2(– 5)
= – 14
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