Depth of Hank descends = The point he reached - the point where he worked initially
= 57 - 10
= 47 ft
Hence, Hank descends 47 ft.
Answer:
x = 10 cm, y = 5 cm gives a minimum area of 300 cm^2.
Step-by-step explanation:
V= x^2y = 500
Surface area A = x^2 + 4xy.
From the first equation y = 500/x^2
So substituting for y in the equation for the surface area:
A = x^2 + 4x * 500/x^2
A = x^2 + 2000/x
Finding the derivative:
dA/dx = 2x - 2000x^-2
dA/dx = 2x - 2000/x^2
This = 0 for a minimum/maximum value of A, so
2x - 2000/x^2 = 0
2x^3 - 2000 = 0
x^3 = 2000/ 2 = 1000
x = 10
Second derivative is 2 + 4000/x^3
when x = 10 this is positive so x = 10 gives a minimum value of A.
So y = 500/x^2
= 500/100
= 5.
7.846 decomposed is:
7 + 0.8 + 0.04 + 0.006
or, to see it more clearly:
7.000 + 0.800 + 0.040 + 0.006
Rounded to the nearest tenth: 7.8
Rounded to the nearest hundredth: 7.85
I hope that's what you meant :)