For the function f = x2y + 2y2x, at the point P(1,3), what is the direction in which the directional derivative is zero?

For the function f = x2y + 2y2x, at the point P(1,3), what is the dire

1.	For the function f = x2y + 2y2x, at the point P(1,3), what is the direction in which the directional derivative is zero?
A.	(-13 hat{i} 24 hat{j} )
B.	(13 hat{i} + 24 hat{j} )
C.	( 13 hat{i} 24 hat{j} )
D.	( 13 hat{i} 24 hat{j} )
Answer» D. ( 13 hat{i} 24 hat{j} )

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