(a) find dy, and (b) evaluate dy for the given value of x and dx... y+xy-x=0...x=0...dx=0.01

Question

anonymous · Answer

$$
dy = \frac{dy}{dx}dx = f'(x)dx
$$In this case: $$
y = f(x) = y+xy-x
$$

anonymous · Answer

So your first task is to find $f'(x)$

anonymous · Answer

Oops, I messed up a bit.

anonymous · Answer

We don't have $y  =f(x)$.  Since we have $$
y+xy-x=0
$$

anonymous · Answer

We have to find $f'(x)$ using implicit differentiation, I believe.

anonymous · Answer

Do you need help with implicit differentiation?

anonymous · Answer

Thanks for your help! I'm just confused about using differentials...using the change in y and change in x as variables....I just don't get it...

anonymous · Answer

Well, when it comes to differentials, remember that $\Delta y$ is the actual change in $y$, where ase $dy$ is a linear approximation of $\Delta y$. Obviously if the function isn't a line, it's going to diverge.

anonymous · Answer

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anonymous · Answer

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