- #1

abdo799

- 169

- 4

## Homework Statement

complete problem attached

## Homework Equations

## The Attempt at a Solution

part I in this question was a bit tricky but i managed to solve it , when i read part II i understood nothing , he usually asks about the tangent not the normal , he asks about the point where the gradient of the normal is maximum and i have no idea how to get this , when i read the answers he said we should differentiate again then = it to 0 to find x , why did this work?