i really need to know as to how to calculate 1) product

Question

i really need to know as to how to calculate

1) product & sum of n integers
2) product & sum of the sqr of n integer
3) product & sum of the cube of n integers
4) product & sum of the first n even integers
5) product & sum of the first n odd integers

need some help pls!!!! if someone can just post the formulas out here....thanks

gsr · Answer

To find the sum of first n - even, odd or all numbers, you can use the formula - 
Sum = (1st term in series + last term)*n/2

Product, I am not aware of any formulae.
Sum of squares/cubes - i'll let someone else give you the correct answer. i don't know upfront.

sushom101 · Answer

To find the sum of first n - even, odd or all numbers, you can use the formula - 
Sum = (1st term in series + last term)*n/2

.........for all numbers do we still need to divide by 2

gsr · Answer

1. Sum of first 10 numbers 1 + 2 + 3 +...+ 10
sum = (1+10)*10/2 = 55
2. Sum of 1st 10 even numbers 2+4+6+...+20 
sum=(2+20)*10/2 = 110
OR
you can write it as 2*(1+2+3+...+10) and use {1}.
3. 3*(1+2+3...+10)...

Hope it is clear.

duttsit · Answer

https://www.mathpages.com/home/kmath279.htm

Titleist · Answer

Here's a link to an interactive website that someone provided earlier that I thought was quite interesting. 

 https://www.cut-the-knot.org/Curriculum/Algebra/Figurate.shtml

pavrnd · Answer

1) product & sum of n integers
S = n(n+1)/2 
P= n!

2) product & sum of the sqr of n integer
S = n(n+1)(2n=1)/6
P = (n!)^2

3) product & sum of the cube of n integers
S =  ^2
P = (n!)^3

4) product & sum of the first n even integers
S = n(n+1) 
P = (n!)(2^n)

5) product & sum of the first n odd integers 
S = n^2
P = (2n!) / (n!)(2^n) 
 = Product of first 2n integers / Product of first n even integers

i really need to know as to how to calculate 1) product

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