Let for and . Then
Let for and . Then
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Let f(x,y)=(x²-y³)/(x²+y²) for (x,y)≠(0,0) and f(0,0)=0. Then (A) f is not continuous at (0,0) (B) fₓ(0,0)=0 (C) f_y(0,0)=-1 (D) fₓ(0,0) does not exist
Also written as: Let f(x,y)=(x^2-y^3)/(x^2+y^2) for (x,y)!=(0,0) and f(0,0)=0. Then
Multivariable calculus has come up 32 times in 7 exams since 2007.
This question is on Partial derivatives and differentiability, part of Multivariable calculus in Mathematics.
Derivatives with respect to one variable at a time, and how they relate to continuity and differentiability.
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Question from the IIT JAM 2023 paper. Solutions are TestStop's own. Not affiliated with or endorsed by any examination authority.