Angel Saijal: MATHS……………………..?
show that square of any positive odd integer is of the form 8q+1 for some integer q.
plz i need explanation…………….
Answers and Views:
Answer by Michael jackson
oh..sorry,im very poor in math,u better ask this ur teacher
[edit] ok, now i think i see what you meant there.
3^2 = 9
8(1) + 1 = 9
5^2 = 25
8(3) + 1 = 25
7^2 = 49
8(6) + 1 = 49
9^2 = 81
8(10) + 1 = 81
11^2 = 121
8(15) + 1 = 121, etc….
Has something to do with:
(odd number)^2 = 8(q) + 1
but the trick is figuring out the relationship between the odd number and q, and it’s just not coming to me in formula form.
the positive odd integer is in the form of (8q+1)
so its square will be 64q^2+1+16q=16q(4q+1)+1.
Here 16q(4q+1) is even and the addition of 1 makes it odd.
so the square is an odd integerAnswer by rishabh agarwal
For example you take 3.square of 3 is 9 and it is of form 8q+1,where q is 1.
Explanation——————————->
Every odd positive integer is of form (2n+1) ,where n ranges from o to infinity.Now when you square this term you get
(2n+1)^2=4n^2+1+4n.
This can be regrouped and can be written as
4n(n+1)+1——————————-(1),
where n ranges from 1 to infinity.Now if n is even or odd then n+1 will be odd or even and the product of odd and even is always even ,so we will be getting an even term.
now n(n+1) is always even we proved it.
Now every even number can be grouped as some 2*q
therefore,n(n+1)=2q.Now substitute this value in equation 1 ,then we will be getting as
(2n+1)^2=4*2q+1
therefore ,(2n+1)^2=8q+1.
Hence explained in detailedAnswer by $# ρ汉$$ΐ☼₪汉个€ ρυ₪נ汉ßΐ๏๏๏ #$
LET a be any positive integer and b = 8
therefore r= 0,1,2,3,4,5,6,7 (since 0<=r<b)
therfore a= bq+r
a= 8q,8q+1,…..8q+7
a (odd)=bq+1,8q+3..8q+7
a square= 64q square+1(m=8q square)
,,,,,=64q square +9+16*3q=8(8q square+24q)+8+1=8(8q square+24q+1)+1
understood
plz best awnser
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