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Which statements are true?
(look at picture)​

Which statements are true? (look at picture)​-example-1
User Orysia
by
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1 Answer

5 votes

Answer:

D is true, E is true, F is true

Explanation:

Hello,

n is an odd number it means that n = 2a+1 where a is integer

A


n^2-1=(2a+1)^2-1=4a^2+4a+1-1=4a(a+1)

this is not an odd number

B


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

this is not an odd number

C


(n-1)^2=(2a+1-1)^2=4a^2

this is not an odd number

D


n^2+2=(2a+1)^2+2=4a^2+4a+1+2=4a^2+4a+3= 2(2a^2+2a+1)+1

so this is an odd number

E


n(n-2)=(2a+1)(2a-1)=4a^2-1=4a^2-2+1=2(2a^2-1)+1

so this is an odd number

F


(n-2)^2=(2a+1-2)^2=(2a-1)^2=4a^2-4a+1 = 2(2a^2-2a)+1

this is an odd number

hope this helps

User Pepuch
by
4.2k points