Is this solution right or not ? Need yr backing

[Mechano]

Is this solution right or not ? Need yr backing

Hello guys,

would you please check the solution attached with this post and whether it's right or wrong ?
if wrong, what's the correct solution

I'm looking forward to get yr backing ASAP

 

[chiro]

Hey Mechano and welcome to the forums.

Looks good to me with the chain rule and proper substitution but its been a while since I've done any vector calculus or line integrals, but based on the identities, the chain rule and the substitution looks good.

Hopefully we can get a few more clarifications here just to be sure.

 

[Mechano]

I'm grateful your quick response Chiro, I"m agree with you, let's waiting the other clarification to be sure of solution's validity

 

[Mechano]

for the same problem above, can you help me to suggest solution to find

\ointgdf

 

[Mechano]

would you please check the attachment, I solved above question and I need your approval