So, f[x] = 1/4x^2 - 1/2Ln(x)
<span>thus f'[x] = 1/4*2x - 1/2*(1/x) = x/2 - 1/2x </span>
<span>thus f'[x]^2 = (x^2)/4 - 2*(x/2)*(1/2x) + 1/(4x^2) = (x^2)/4 - 1/2 + 1/(4x^2) </span>
<span>thus f'[x]^2 + 1 = (x^2)/4 + 1/2 + 1/(4x^2) = (x/2 + 1/2x)^2 </span>
<span>thus Sqrt[...] = (x/2 + 1/2x) </span>
Given:
The formula for total cost is

where, p is the price of item and s is the sales tax rate (as a percent).
You pay $14.77 for an item priced at $14.
To find:
The the tax rate.
Solution:
You pay $14.77 for an item priced at $14. So,
Total cost (T) = $14.77
Price of item (p) = $14
Putting T=14.77 and p=14 in given formula, we get



Multiply both sides by 100.

Divide both sides by 14.


Therefore, the tax rate is 5.5%.
Let X be the number of lightning strikes in a year at the top of particular mountain.
X follows Poisson distribution with mean μ = 3.8
We have to find here the probability that in randomly selected year the number of lightning strikes is 0
The Poisson probability is given by,
P(X=k) = 
Here we have X=0, mean =3.8
Hence probability that X=0 is given by
P(X=0) = 
P(X=0) = 
P(X=0) = 0.0224
The probability that in a randomly selected year, the number of lightning strikes is 0 is 0.0224
Triangle ABD and ADC are righttriangles so u can use the Pythagorean theorem/triples. the triples are 3/4/5 and 5/12/13. 12 is 4x3, and 15 is 5x3, so BD is 3x3, which is 9. AC is 13, as it is part of the Pythagorean’s triples