It's unclear what the planes are supposed to be, so I'll take
and
with
.
The cross sections are disks with diameter
, so each disk of thickness
has a volume of

Then taking infinitesimally thin disks, we find the solid has a volume of

Since

and


it follows that the volume is



3. A and 4. C .....I think
Answer:
a = 3
b = 2
c = 0
d = -4
Step-by-step explanation:
Form 4 equations and solve simultaneously
28 = a(2)³ + b(2)² + c(2) + d
28 = 8a + 4b + 2c + d (1)
-5 = -a + b - c + d (2)
220 = 64a + 16b + 4c + d (3)
-20 = -8a + 4b - 2c + d (4)
(1) + (4)
28 = 8a + 4b + 2c + d
-20 = -8a + 4b - 2c + d
8 = 8b + 2d
d = 4 - 4b
Equation (2)
c = -a + b + d + 5
c = -a + b + 4 - 4b+ 5
c = -a - 3b + 9
28 = 8a + 4b + 2c + d (1)
28 = 8a + 4b + 2(-a - 3b + 9) + 4 - 4b
28 = 6a - 6b + 22
6a - 6b = 6
a - b = 1
a = b + 1
220 = 64a + 16b + 4c + d (3)
220 = 64(b + 1) + 16b + 4(-b - 1 - 3b + 9) + 4 - 4b
220 = 60b + 100
60b = 120
b = 2
a = 2 + 1
a = 3
c = -3 - 3(2) + 9
c = 0
d = 4 - 4(2)
d = -4
Answer:
the factors of f(x)=x^3+8x^2+5x-50 are (x-2)(x+5)(x+5)
Step-by-step explanation:
We need to factorise the function 
If a number is a factor of this function than it must be completely divisible by last co-efficient. Our last co-efficient is -50
Checking few numbers:

So, f(2)=0 which means x-2 is a factor of the given function. Now we will perform long division of
by (x-2) to find other factors
The long division is shown in figure attached.
After long division we get: 
The equation
can be further simplified as: (x+5)(x+5) or (x+5)^2
So, the factors of f(x)=x^3+8x^2+5x-50 are (x-2)(x+5)(x+5)