Explanation:
Let
and
. The differential volume dV of the cylindrical shells is given by
![dV = 2\pi x[f(x) - g(x)]dx](https://tex.z-dn.net/?f=dV%20%3D%202%5Cpi%20x%5Bf%28x%29%20-%20g%28x%29%5Ddx)
Integrating this expression, we get
![\displaystyle V = 2\pi\int{x[f(x) - g(x)]}dx](https://tex.z-dn.net/?f=%5Cdisplaystyle%20V%20%3D%202%5Cpi%5Cint%7Bx%5Bf%28x%29%20-%20g%28x%29%5D%7Ddx)
To determine the limits of integration, we equate the two functions to find their solutions and thus the limits:

We can clearly see that x = 0 is one of the solutions. For the other solution/limit, let's solve for x by first taking the square of the equation above:

or

Since we are rotating the functions around the y-axis, we are going to use the x = 25 solution as one of the limits. So the expression for the volume of revolution around the y-axis is




a. We can parameterize
by


with
. Then

b. We can parameterize the opposite direction by instead setting


with
. Then

which gives the same value as in part (a).
Dfyujb. Hgdgyyf hedge. 4+9-(/4)
Answer:
a = - 2 and b = - 3
Step-by-step explanation:
Distribute the parenthesis on the left side then compare like terms on both sides.
4(3x - 6) - 7(2x + b)
= 12x - 24 - 14x - 7b
= - 2x - 24 - 7b
Compare to right side ax - 3
For the 2 sides to be equal then
- 2x = ax ⇒ a = - 2
and
- 24 - 7b = - 3 ( add 24 to both sides )
- 7b = 21 ( divide both sides by - 7 )
b = - 3
The sum of angle around a point equal 360°
so (BOA) = 360-250=110°
and the sum of angle in the shape CAOB = 360°
so BCA = 360-(110+90+90)= 70°
THE ANSWER IS C.70°