Answer:
22.5
Step-by-step explanation:
If you expand the series, you can see the first few terms of the series:
- Putting 1 in ,
- Putting 2 in ,
- Putting 3 in ,
- Putting 4 in ,
We can see the series is 0, 0.5, 1, 1.5, ....
This is an arithmetic series with common difference (the difference in 2 terms) 0.5 and first term 0.
We know formula for sum of arithmetic series:
Where,
- denotes the nth partial sum
- is the first term (in our case it is 0)
- is the term (in our case it is 10 since we want to find 10th partial sum -- sum until first 10 terms)
- is the common difference (difference in term and the previous term) (in our case it is 0.5)
Substituting these into the formula, we get the 10th partial sum to be:
So the sum of the first 10 terms is 22.5. Third answer choice is right.
Answer:
2 + 2
Step-by-step explanation:
= = 2
Answer:
Step-by-step explanation:
0.0057
first number
5
then the rest
7
equal
5.7
There's <u>three</u> zeros <u>behind</u> the number 5 which mean it will be -3
final answer
another example and it will be clear
0.0000403
first number
4
then the rest
03
equal
4.03
There's <u>five</u> zeros <u>behind</u> the number 4 which mean it will be -5
final answer
There are infinitely many solutions.
Algebraically, we can eliminate and try to solve for :
Then
which is the equation of an ellipse.
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