The answer should be 1 and three
Hello from MrBillDoesMath!
Answer:
a^6 + 4 a^5 + 5 a^4 - 5 a^2 - 4 a - 1
Discussion:
You may need to clean things up a bit but suppose that
S(1) = a-1
S(2) = a^2 -1
Since this is a geometric series, the geometric ratio is given by
S(2)/ S(1) = (a^2 -1)/ (a-1)
= (a+1)(a-1)/ (a-1)
= a+1
Conclusion:
S(2) = (a+1) S(1) = (a+1) (a-1)
S(3) = (a+1) S(2) = (a+1) (a+1) (a-1) = (a+1)^ (3-1) (a-1)
S(4) = (a+1) S(3) = (a+1) * (a+1)^2 (a-1) ) = (a+1)^(4-1) (a-1)
in general.....
S(n) = (a+1)^ (n-1) (a-1)
So
S(6) = (a+1)^ (6-1) (a-1)
= (a-1) (a+1) ^ 5
= a^6 + 4 a^5 + 5 a^4 - 5 a^2 - 4 a - 1
Hope I didn't screw something here!
Thank you,
MrB
Answer:
170.25
Step-by-step explanation:
It's a bit tricky to do not on plain paper, but here:
Just assume the long division symbol looks right
_1_7_0_.25
4 ) 681
-4
2 8
-2 8
0 1
The remainder is "1", so you'll just have to write that as either a fraction or decimal, whatever is assigned.
Fraction: 170 1/4
Decimal: 170.25
Answer:
Solution : Volume = 96/5π
Step-by-step explanation:
If we slice at an arbitrary height y, we get a circular disk with radius x, where x = y^(1/3). So the area of a cross section through y should be:
A(y) = πx^2 = π(y^(1/3))^2 = πy^(2/3)
And now since the solid lies between y = 0, and y = 8, it's volume should be:
V = ∫⁸₀ A(y)dy (in other words ∫ A(y)dy on the interval [0 to 8])
=> π ∫⁸₀ y^(2/3)dy
=> π[3/5 * y^(5/3)]⁸₀
=> 3/5π(³√8)⁵
=> 3/5π2^5
=> 96/5π ✓
