Question

help, don't know how solution was achieved.

Answer 1

\[\left(\begin{matrix}-\frac{ 1 }{ x(x+h)} \\ \end{matrix}\right) = \frac{ -1 }{ x ^{2} }\]

Answer 2

@ghazi @zordoloom

Answer 3

take the limit when h tends to zero

Answer 4

Can be possible only if h tends to zero...

Answer 5

yes its meant to be the limit.. but h never becomes zero so how do we get to x^2?

Answer 6

well h never becomes zero but when h is just before zero then it can approximated as zero and then you can substitute h=0 and you can get your desired result

Answer 7

Its not that h actually becomes 0 .... The idea of taking limits discusses that h is a really small number which can approximately be seen as 0.

Answer 8

thank you!