Question

Zx-Zy=Zx-ythen Dy/DX at X=y=z​

Answer 1

here X=y=z

so,

Zx - Zy=Z(x-y)

=Z(0)

=0

$zx - y = 0 \\ zx = y \\ x = \frac{y}{z}$

multiply both sides with D/D

$\frac{dx}{d} = \frac{dx}{dy} \\ \frac{dx}{dy} = 1$

so,the answer is 1

I hope that it will help you.......