I am sure the correct answer is x=0.38629436…hope this help you
Answer:

Step-by-step explanation:
<u>Surface Areas
</u>
Is the sum of all the lateral areas of a given solid. We need to compute the total surface area of the given prism. It has 5 sides, two of them are equal (top and bottom areas) and the rest are rectangles.
Computing the top and bottom areas. They form a right triangle whose legs are 4.5 mm and 6 mm. The area of both triangles is

The front area is a rectangle of dimensions 7.7 mm and 9 mm, thus

The back left area is another rectangle of 4.5 mm by 9 mm

Finally, the back right area is a rectangle of 6 mm by 9 mm

Thus, the total surface area of the prism is


Answer:
- Question 1a. i)

- Question 1a. ii)

- Question 1b)

Explanation:
<u><em>Question 1 a. i) Find the value of x.</em></u>

For the smalll triangle you can write:

For tthe big triangle:

Substitute:

Solve for x:

<u><em>Question 1a ii) Find the volume of the frustrum</em></u>
- Find the volume of a cone with height = 2.7m + 1.8m = 4.5m, and radius = 2.5m
Formula:

Substitute:

- Find the volume of a cone with heigth = 1.8m and radius = 1m

- Subtract the volume of the small cone from the volume of the big cone

<u><em>Question 1b. Calculate the volume of the bin</em></u>
<u>i) Upper frustrum</u>
This is the same frustrum from the equation of above, thus ist volume is 27.6m³.
<u>ii) Lower frustrum</u>




<u>iii) Add the volume of the two frustrums</u>
Answer:
e and c
Step-by-step explanation:
<span>since sin and cos = each other at pi/4; take your integrals from 0 to pi/4
</span><span>[S] cos(t) dt - [S] sin(t) dt ;[0,pi/4]
</span>
<span>to revolve it around the x axis;
we do a sum of areas
[S] 2pi [f(x)]^2 dx
</span>
<span>take the cos first and subtract out the sin next; like cutting a hole out of a donuts.
</span><span>pi [S] cos(x)^2 dx - [S] sin(x)^2 dx ; [0,pi/4]
</span>
<span>cos(2t) = 2cos^2 - 1
cos^2 = (1+cos(2t))/2
</span>
<span>1/sqrt(2) - (-1/sqrt(2) +1)
1/sqrt(2) + 1/sqrt(2) -1
(2sqrt(2) - sqrt(2))/sqrt(2) = sqrt(2)/sqrt(2) = 1</span>