Answers:
a = 2
b = 3
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Explanation:
Plug in x = 0 and y = 2 to find that
y = a*b^x
2 = a*b^0
2 = a*1
2 = a
a = 2
Then plug in x = 3 and y = 54 to determine the value of b
y = a*b^x
y = 2*b^x
54 = 2*b^3
2b^3 = 54
b^3 = 54/2
b^3 = 27
b = (27)^(1/3)
b = 3
So we have y = a*b^x update to y = 2*3^x
Answer:
The volume of the ball with the drilled hole is:

Step-by-step explanation:
See attached a sketch of the region that is revolved about the y-axis to produce the upper half of the ball. Notice the function y is the equation of a circle centered at the origin with radius 15:

Then we set the integral for the volume by using shell method:

That can be solved by substitution:

The limits of integration also change:
For x=5: 
For x=15: 
So the integral becomes:

If we flip the limits we also get rid of the minus in front, and writing the root as an exponent we get:

Then applying the basic rule we get:

Since that is just half of the solid, we multiply by 2 to get the complete volume:


5^-2=1/5^2=1/25
2^-4=1/2^4=1/16
5^3=5*5*5=125
2^5=2*2*2*2*2=32
Hope this helped :)
For number 7 what is the formula for volume of a cube