Answer:
The answer to your question is At = 48 + 36
Step-by-step explanation:
Area = Area of the base + Lateral area
a) Area of the base
Area = length x height / 2
length = 12
height² = 12² - 6²
= 144 - 36
= 108
height = = 6
Area = 12 x 6
= 36
b) Lateral area
height² = 10² - 6²
= 100 - 36
= 64
height = 8
Area = 12 x 8/2
= 48
c) Total area
At = 48 + 36
See attached for a sketch of some of the cross sections.
Each cross section has area equal to the square of the side length, which in turn is the vertical distance between the curve y = √(x + 1) and the x-axis (i.e. the distance between them that is parallel to the y-axis). This distance will be √(x + 1).
If the thickness of each cross section is ∆x, then the volume of each cross section is
∆V = (√(x + 1))² ∆x = (x + 1) ∆x
As we let ∆x approach 0 and take infinitely many such cross sections, the total volume of the solid is given by the definite integral,
