Question

Arithmetic Series?

Answer 1

@iGreen Question ?

Answer 2

I have no idea what to do..

Answer 3

Use the fact that:

sum of integers from 1 to x = x(x+1)/2

Answer 4

You can simplify the sum as:

\[\large{\sum_{n=1}^{5}(2n+3)}\]

\[\large{=2\sum_{n=1}^{5}n + 3\sum_{n=1}^{5}1}\]

Answer 5

Now do you think you can solve it ?

Answer 6

No..could you explain the whole thing to me? 'Cause this is the first time I learned this stuff.

Answer 7

Which step ?

Answer 8

Lol, I'm completely lost.

Answer 9

@iGreen , which step you are having problem with ??

Answer 10

Its okay

Answer 11

Lets start from beginning.

Answer 12

u have
sumation 2n+3 from 1 to 5
(2(1)+3)+(2(2)+3)+(2(3)+3)+(2(4)+3)+(2(5)+3)

Answer 13

@iGreen how comfortable are you with integration ?

Answer 14

Okay forget about integration. Lets try something new

Answer 15

See, \(\sum\) means adding.

Answer 16

But adding a set of numbers who are following a particular.. uhm.. formula we can say.

For example, if I ask you to add all the natural numbers from 1 to 10 (including both 1 to 10) which are of the form "n" where n is a natural number.

Answer 17

Proceed step by step.

n means natural number and power 1.

Answer 18

So, is 1 of the form n ?

Answer 19

Lets check it:

1. Is 1 a natural number?

2. Does 1 have power 1 ?

Answer 20

@iGreen answer the above questions point by point.

Answer 21

that was amazing help ^

Answer 22

Thanks a lot @ikram002p :)

Answer 23

^^

Answer 24

1. Is 1 a natural number? Yes.

2. Does 1 have power 1 ? I don't know what you mean..

Answer 25

I mean does 1 have the form : n

Answer 26

For example if I say does 2^2 has the form n^2. Yes.

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