If f(Z) is an analytical function and (r, θ) denotes the polar co-ord

1.	If f(Z) is an analytical function and (r, θ) denotes the polar co-ordinates, then:
A.	\(\frac {\partial u}{\partial r} = \frac 1 r \frac {\partial v}{\partial \theta}\) and \(\frac {\partial v}{\partial r} = \frac {-1}{r} \frac {\partial u}{\partial \theta}\)
B.	\(\frac {\partial u}{\partial r} = \frac {-1} r \frac {\partial v}{\partial \theta}\) and \(\frac {\partial u}{\partial r} = \frac {1} r \frac {\partial v}{\partial \theta}\)
C.	\(\frac {\partial u}{\partial r} = -r \frac {\partial v}{\partial \theta}\) and \(\frac {\partial v}{\partial r} = r \frac {\partial u}{\partial \theta}\)
D.	\(\frac {\partial u}{\partial r} = r \frac {\partial v}{\partial \theta}\) and \(\frac {\partial v}{\partial r} = -r \frac {\partial u}{\partial \theta}\)
Answer» B. \(\frac {\partial u}{\partial r} = \frac {-1} r \frac {\partial v}{\partial \theta}\) and \(\frac {\partial u}{\partial r} = \frac {1} r \frac {\partial v}{\partial \theta}\)

Discussion

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