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3 years ago

Please help on one math question

Mathematics

2 answers:

Andreyy893 years ago

8 0

Answer:

the answer is 225 :)))))))))))))))))))

Step-by-step explanation:

kipiarov [429]3 years ago

6 0

Hello from MrBillDoesMath!

Answer:

225

Discussion:

Sum ( 2n - 1) from n = 1 to 15

= Sum(2n) - Sum(1) from n = 1 to 15

= 2 Sum(n) - Sum(1) from n = 1 to 15

= 2* 15(15+1)/2 - (1 + 1 + .. + 1)

The first value comes from the fact that the sum of the first n integers is n(n+1)/2. The latter value sums 15 1's.

= 2 * 15 * 16/2 - 15 => 2/2 = 1

= 15*16 - 15 => 15*16 = 240

= 240 - 15

= 225

Thank you,

MrB

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Pavlova-9 [17]

Answer:

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Step-by-step explanation:

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2 years ago

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Zinaida [17]

Answer:

Step-by-step explanation:

Remark

Read the following carefully.

There is a beautiful theorem that has to do with the endpoints of two angles sharing the same endpoints.

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1 year ago

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Answer:

Step-by-step explanation:

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Step-by-step explanation:

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