Partial derivative is derivative over only 1 variable.
here we have 2 variables so it depends on which variable you want to make partial derivative.
case 1.
df/dx = -3y
case 2
df/dy = 5y^4 - 3x
Answer:
They encircle the planet
times.
Step-by-step explanation:
Consider the provided information.
We have 2.5 mole of dust particles and the Avogadro's number is 
Thus, the number of dust particles is:

Diameter of a dust particles is 10μm and the circumference of earth is 40,076 km.
Convert the measurement in meters.
Diameter: 
If we line up the particles the distance they could cover is:

Circumference in meters:

Therefore,

Hence, they encircle the planet
times.
Answer:
y=-10x
Step-by-step explanation:
y=-10x
y/x=-10
CP - the cost of painting the house for Painting USA company [$]
cP = 75 + 25 * 25 = 75 + 625 = 700 [$]
cU - the cost of painting the house for Upscale Home Painting company [$]
cU = 0 + 40 * 25 = 1000 [$]
cP < cU
The most cost effective is Painting USA company.
n - number of houres required to paint the house if the same cost for both companies
75 + 25 * n = 40 * n
40 n - 25n = 75
15n = 75 /:15
n = 5
The cost of paining the house is the same for both companies if the number of houres required to paint the house is 5.