I wasn't able to understand this topic of reflection of straight line and it's maxima and minima

Reflection of pts wrt a line implies the picture of the fact of the matter is shaped at an equivalent dist from the line on the opposite side. 

for instance, impression of (4,0) wrt x=0 is (- 4,0) 

Maxima and minima are separately the biggest and littlest estimation of the capacity in a given range. In the event that the maximum or min is max or min all through the entire func then it is called worldwide max or min, else it is called neighborhood maxima or nearby minima.[Ans]