A/8 +1= 4 because a is devided by 8 then you have to add one to equal 4
Answer:
x = ± 
Step-by-step explanation:
Given
x² = 20 ( take the square root of both sides )
x = ± 
which can be simplified to
x = ± 2
[ ± means plus or minus ]
The expected length of code for one encoded symbol is

where
is the probability of picking the letter
, and
is the length of code needed to encode
.
is given to us, and we have

so that we expect a contribution of

bits to the code per encoded letter. For a string of length
, we would then expect
.
By definition of variance, we have
![\mathrm{Var}[L]=E\left[(L-E[L])^2\right]=E[L^2]-E[L]^2](https://tex.z-dn.net/?f=%5Cmathrm%7BVar%7D%5BL%5D%3DE%5Cleft%5B%28L-E%5BL%5D%29%5E2%5Cright%5D%3DE%5BL%5E2%5D-E%5BL%5D%5E2)
For a string consisting of one letter, we have

so that the variance for the length such a string is

"squared" bits per encoded letter. For a string of length
, we would get
.
If you change the point's x-coordinate, the point will move either to the left or the right, depending on if the number you change is negative or positive.