(a) First find the intersections of

and

:

So the area of

is given by

If you're not familiar with the error function

, then you will not be able to find an exact answer. Fortunately, I see this is a question on a calculator based exam, so you can use whatever built-in function you have on your calculator to evaluate the integral. You should get something around 0.5141.
(b) Find the intersections of the line

with

.

So the area of

is given by


which is approximately 1.546.
(c) The easiest method for finding the volume of the solid of revolution is via the disk method. Each cross-section of the solid is a circle with radius perpendicular to the x-axis, determined by the vertical distance from the curve

and the line

, or

. The area of any such circle is

times the square of its radius. Since the curve intersects the axis of revolution at

and

, the volume would be given by
Answer:
Joshua worked 4 hours and luke worked 7
Step-by-step explanation:
25x + 35x +105 = 345
60x = 345 - 105
60x = 240
x = 240/60
x = 4 hours
Answer:
-9
Step-by-step explanation:
-9+6=-3
Answer:
the answer is $8.29
Step-by-step explanation:
1.60 marked up by 60% in decimal form is .60
multiply that .60 by 1.60 and you get .64
you add .64 to 1.60 and you get 2.56
you multiply 2.56 by 3 and you get 7.68
you have a 8% sales tax so you multiply 0.08 by 7.68
you will get .61 you add that to 7.68 to get $8.29