If a is a negative integer, is |a|+|b| an even integer?
(1) x^a·x^b=1
(2) a≠−1
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(1) x^a·x^b=1
(2) a≠−1
[Reveal] Spoiler:
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I answered A because x^a times x^b = 1 means that x^a = 1/x^b or that a = -b. Therefore, a and b are the same number with opposite signs, thus |a| + |b| must be even because odd+odd=even and even+even=even. If a and b are same number with opposite signs, they cannot be one odd and one even. therefore 1 sufficient
Obviously 2 isnt
I answered A because x^a times x^b = 1 means that x^a = 1/x^b or that a = -b. Therefore, a and b are the same number with opposite signs, thus |a| + |b| must be even because odd+odd=even and even+even=even. If a and b are same number with opposite signs, they cannot be one odd and one even. therefore 1 sufficient
Obviously 2 isnt
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