COULD be an odd

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COULD be an odd

by sanju09 » Fri Jun 18, 2010 4:56 am
If a and b are both even numbers, which of the following COULD be an odd integer?
(A) (a + b) ^2
(B) a^2 + b^2
(C) (a + 1) ^2 + (b + 1) ^2
(D) (a + 1) (b + 1) - 1
(E) (a + 1) / (b + 1)
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by kvcpk » Fri Jun 18, 2010 5:01 am
(a+1)/(b+1) could be odd when a=b

answer E

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by amising6 » Fri Jun 18, 2010 5:27 am
If a and b are both even numbers, which of the following COULD be an odd integer?
(A) (a + b) ^2
(B) a^2 + b^2
(C) (a + 1) ^2 + (b + 1) ^2
(D) (a + 1) (b + 1) - 1
(E) (a + 1) / (b + 1)

we will solve it by using option
lets keep this concept in mind:
even +even=even
even*odd=even


a)(a+b)^2 = a^2+b^2+2ab if a and b both are even all the term individally will be even
b)again square of even and then sum of even numbers will result in even number
c)i ndividually both term will give odd but odd+odd will result in even number
d)i ndividually both term will give odd but odd -odd will again give even
e) will give fraction unless both a and b are same in this case you will get 1 odd
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