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Anika [276]
3 years ago
6

How do i find a formula for "1+3+5+7+......+(2n-1)

Mathematics
1 answer:
nata0808 [166]3 years ago
7 0

Answer:

Step-by-step explanation:

common difference d=3-1=2

first term a=1

an=a+(n-1)d

2n-1=1+(l-1)2

2n-1=1+2l-2

2n-1=2l-1

l=n

(i used l for number of terms)

number of terms=n

S_{n}=\frac{n}{2} (first ~term+last~term)\\=\frac{n}{2} (1+2n-1)\\=n^2

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3 years ago
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the marks in an examination for a Physics paper have normal distribution with mean μ and variance σ2 . 10% of the students obtai
Blababa [14]

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3 years ago
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8 0
2 years ago
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tamaranim1 [39]
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Hope this helps!
7 0
3 years ago
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