I think the question is: 2S = 2U + 2V
Answer D
tricky one
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Source: Beat The GMAT — Problem Solving |
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tohellandback
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Easy method:
plugin numbers
16=8+8
1-false
2-false 3-true
Answer D
tricky method:
2^S=2^U + 2^V
2^S=2^V(2^(U-V)+1)
2^(S-V)= 2^(U-V) +1
now 2^(U-V) +1 will be
ODD- when U>V
or, 1+ (a fraction) when U<V
but on the LHS, we have even when s>V or a fraction less than 1 when S<V
so above cases are not possible.
Only possibility is U=V where 2^(U-V) +1 will be even
so 2^(U-V) +1= 2 when U=V
so S-V must be 1
S>V
answer D
plugin numbers
16=8+8
1-false
2-false 3-true
Answer D
tricky method:
2^S=2^U + 2^V
2^S=2^V(2^(U-V)+1)
2^(S-V)= 2^(U-V) +1
now 2^(U-V) +1 will be
ODD- when U>V
or, 1+ (a fraction) when U<V
but on the LHS, we have even when s>V or a fraction less than 1 when S<V
so above cases are not possible.
Only possibility is U=V where 2^(U-V) +1 will be even
so 2^(U-V) +1= 2 when U=V
so S-V must be 1
S>V
answer D
The powers of two are bloody impolite!!
