Differentiation 5

√x²+y² = ae^{tan^-1(y/x)} , a>0 then y^''(0) :

a) a/2.e^-Ï€/2
b) ae^Ï€/2
c) -2/a.e^-Ï€/2
d) none

2 Answers

substituting y=xz does the trick

then dy/dx=xdz/dx+z

and so on

@ shanks...

i think it is not a problem of differential equatn...bt a problem of differenciation...

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