Surface Integral Proof











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First of all, this is a homework question but my course textbook was not helpful and I couldn't find any similar material online so I thought it was fair to ask it on MSE.



Here is the question:
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I am having trouble understanding what it is asking... in particular, what exactly is "u" and how should I begin this proof?



Any help would be much appreciated,



Thank you!






calculus







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  • Which part of "Suppose $uin C^1(B_1)$" is difficult for you?
    – John Douma
    yesterday










  • I haven't seen that notation before so I'm not sure what it means, I'm guessing it means any point inside the ball of radius < 1?
    – Thomas
    yesterday












  • Your instructor should have told you what a $C^1$ function is. In this case, $u$ is not a point in the disk; it is a function on the disk whose first first derivative is continuous. Likewise, in part b, a $C^2$ function is a function whose second derivative is continuous.
    – John Douma
    yesterday















up vote
0
down vote

favorite












First of all, this is a homework question but my course textbook was not helpful and I couldn't find any similar material online so I thought it was fair to ask it on MSE.



Here is the question:
Photo



I am having trouble understanding what it is asking... in particular, what exactly is "u" and how should I begin this proof?



Any help would be much appreciated,



Thank you!






calculus







share|cite|improve this question






















  • Which part of "Suppose $uin C^1(B_1)$" is difficult for you?
    – John Douma
    yesterday










  • I haven't seen that notation before so I'm not sure what it means, I'm guessing it means any point inside the ball of radius < 1?
    – Thomas
    yesterday












  • Your instructor should have told you what a $C^1$ function is. In this case, $u$ is not a point in the disk; it is a function on the disk whose first first derivative is continuous. Likewise, in part b, a $C^2$ function is a function whose second derivative is continuous.
    – John Douma
    yesterday













up vote
0
down vote

favorite









up vote
0
down vote

favorite











First of all, this is a homework question but my course textbook was not helpful and I couldn't find any similar material online so I thought it was fair to ask it on MSE.



Here is the question:
Photo



I am having trouble understanding what it is asking... in particular, what exactly is "u" and how should I begin this proof?



Any help would be much appreciated,



Thank you!






calculus







share|cite|improve this question













First of all, this is a homework question but my course textbook was not helpful and I couldn't find any similar material online so I thought it was fair to ask it on MSE.



Here is the question:
Photo



I am having trouble understanding what it is asking... in particular, what exactly is "u" and how should I begin this proof?



Any help would be much appreciated,



Thank you!






calculus




calculus






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share|cite|improve this question











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Thomas

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  • Which part of "Suppose $uin C^1(B_1)$" is difficult for you?
    – John Douma
    yesterday










  • I haven't seen that notation before so I'm not sure what it means, I'm guessing it means any point inside the ball of radius < 1?
    – Thomas
    yesterday












  • Your instructor should have told you what a $C^1$ function is. In this case, $u$ is not a point in the disk; it is a function on the disk whose first first derivative is continuous. Likewise, in part b, a $C^2$ function is a function whose second derivative is continuous.
    – John Douma
    yesterday


















  • Which part of "Suppose $uin C^1(B_1)$" is difficult for you?
    – John Douma
    yesterday










  • I haven't seen that notation before so I'm not sure what it means, I'm guessing it means any point inside the ball of radius < 1?
    – Thomas
    yesterday












  • Your instructor should have told you what a $C^1$ function is. In this case, $u$ is not a point in the disk; it is a function on the disk whose first first derivative is continuous. Likewise, in part b, a $C^2$ function is a function whose second derivative is continuous.
    – John Douma
    yesterday
















Which part of "Suppose $uin C^1(B_1)$" is difficult for you?
– John Douma
yesterday




Which part of "Suppose $uin C^1(B_1)$" is difficult for you?
– John Douma
yesterday












I haven't seen that notation before so I'm not sure what it means, I'm guessing it means any point inside the ball of radius < 1?
– Thomas
yesterday






I haven't seen that notation before so I'm not sure what it means, I'm guessing it means any point inside the ball of radius < 1?
– Thomas
yesterday














Your instructor should have told you what a $C^1$ function is. In this case, $u$ is not a point in the disk; it is a function on the disk whose first first derivative is continuous. Likewise, in part b, a $C^2$ function is a function whose second derivative is continuous.
– John Douma
yesterday




Your instructor should have told you what a $C^1$ function is. In this case, $u$ is not a point in the disk; it is a function on the disk whose first first derivative is continuous. Likewise, in part b, a $C^2$ function is a function whose second derivative is continuous.
– John Douma
yesterday















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