Answer:
The integral diverges
Step-by-step explanation:
∫₋₁¹ 10/x² dx
There is a discontinuity in the function at x = 0. Splitting this into two integrals:
∫₋₁⁰ 10/x² dx + ∫₀¹ 10/x² dx
-10/x |₋₁⁰ + -10/x |₀¹
∞
1. You have that:
- The homeowner<span> want the length of the swimming pool to be 4 feet longer than its width.</span>
- He wants to surround it with a concrete walkway 3 feet wide.
- He can only afford 300 square feet of concrete for the walkway.
2. Therefore, the tota area is:
At=L2xW2
L2 is the lenght of the walkway (L2=L1+3+3⇒L2=(W1+4+6)⇒L2=W1+10).
W2 is the width of the walkway (W1+3+3⇒W2=W1+6)
3. The area of the walkway is:
A2=At-A1
A2=300 ft²
4. Therefore, you have that the width of the swimming pool is:
A2=(W1+10)(W1+6)-(W1+4)(W1)
300=(W1²+6W1+10W1+60)-(W1²+4W1)
W1²+16W1+60-W1²-4W1-300=0
12W1-240=0
W1=240/12
W1=20 ft
5. And the length is:
L1=W1+4
L1=20+4
L1=24 ft
For this case we must factor the following expression:
Rewriting the expression:
We factor using the formula of the square difference:
Where:
So:
From the second term we have:
Finally, the factored expression is:
Answer:
Answer:
21 kWh
Step-by-step explanation:
1. Subtract 25% from the original amount.
25% of 28 kWh is ...
0.25 × 28 kWh = 7.00 kWh
Subtracting this from 28 kWh, we find the usage after reduction to be ...
28 kWh - 7 kWh = 21 kWh
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2. We know that if we reduce 100% of a quantity by 25%, then the resulting amount is (100 -25)% = 75% of the original. As a fraction, this is 75/100 = 3/4 of the original amount. Then the reduced usage is ...
(3/4) × (28 kWh) = 3·(7·4)/4 kWh = 3·7 kWh = 21 kWh
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Mario must reduce his usage to 21 kWh or less.
C
the sum to infinity of a geometric series = 
where a is the first term and r the common ratio
= 
= 81 × 3 = 243
