Section -2 how numbers are stored in memory

#1

as mentioned in this video when we took example of 8 bits, we observed that the largest number that can be formed is 128 and smallest no is -128 when MSB is taken as 0 and 1 respectively. But at 7:08(timestamp of video) why took 127 in generalised form instead of 128 as n in the range for calculating total numbers in the formula 2*n+1

#2

Hey @WolfShot
128 is actually -128
10000000// Msb is 1 its denote negative number
After 2S compliment
10000000 // -128