<h2>9.</h2><h3>Given</h3>
<h3>Find</h3>
- linear approximation to the volume when the radius increases 0.4 cm
<h3>Solution</h3>
The equation for volume of a sphere is
... V = (4/3)π·r³
Differentiating gives
... dV = 4π·r²·dr
Filling in the given numbers gives
... change in volume ≈ 4π·(15 cm)²·(0.4 cm)
... = 360π cm³ ≈ 1130.97 cm³ . . . . . . volume of layer 4mm thick
<h2>11.</h2><h3>Given</h3>
- an x by x by 2x cuboid with surface area 129.6 cm²
- rate of change of x is 0.01 cm/s
<h3>Find</h3>
<h3>Solution</h3>
The area is that of two cubes of dimension x joined together. The area of each such cube is 6x², but the two joined faces don't count in the external surface area. Thus the area of the cuboid is 10x².
The volume of the cuboid is that of two cubes joined, so is 2x³. Then the rate of change of volume is
... dV/dt = (d/dt)(2x³) = 6x²·dx/dt
We know x² = A/10, where A is the area of the cuboid, so the rate of change of volume is ...
... dV/dt = (6/10)A·dx/dt = 0.6·(129.6 cm²)(0.01 cm/s)
... dV/dt = 0.7776 cm³/s
Answer:
5) 8/17 = .471
7) 8/17 = .471
8) 15/17 = .88
Step-by-step explanation:
hope that helps
Apply Pythagoras:
length = sqrt( (10--4)² + (6-3)² ) = sqrt(205)
Answer:
Step-by-step explanation:
Picture 1
In right triangle ABC,
Side AB is the opposite side of angle C.
Picture 2
In triangle MKL,
tan(∠M) = 
= 
= 
Option (1) is the answer.
Picture 3
In ΔXYZ,
sin(∠Z) = 
= 
For the length of XY we will apply Pythagoras theorem in ΔXYZ,
XZ² = XY² + YZ²
XY² = XZ² - YZ²
= (40)² - (32)²
XY = √576
= 24
sin(Z) = 
sin(Z) = 
Picture 4
In right triangle DEF,
Cos(D) = 
= 
= 
= 
Picture 5
In ΔABC,
tan(63°) =
tan(63°) = 
AB = 
AB = 
AB = 4.0762 ≈ 4 m
Option (3) will be the answer.
Answer:
to the tenths place, 32.86
Step-by-step explanation: It is because money is always rounded to the tenths place
