Let .
Find the change in , when and
Find the differential when and
can i get some help with this please?
thank you
Currently, $\displaystyle y = f(x) $
So we can say that $\displaystyle y + \Delta y = f(x+ \Delta x) $
We can then re-write this as: $\displaystyle \Delta y = f(x+\Delta x) - y $
And we know that $\displaystyle y = f(x) $, so we can say:
$\displaystyle \Delta y = f(x+\Delta x) - f(x) $
We know that $\displaystyle f(x) = 4 \sqrt{x} $
So:
$\displaystyle \Delta y = 4 \sqrt{x + \Delta x} - 4 \sqrt{x} $
For the second part, just differentiate it and then take it from there.