if x is an integer, is 9^x + 9^(-x) = b?
1) 3^x + 3(-x) = sqrt(b+2)
2) x > 0 = b
I understand and can solve (1)
However what is 2)
In the explanation OG says that the given info is NOT SUFFICIENT.
Can somenody please explain what this expression means ??
If i assume that expression means
x>0 and b=0 then
9^x + 9^(-x) = 0 ?
Ans is No as power of 9 or 1/9 will always be +ve and expression will never be 0. Hence should be SUFFICIENT.
somebody Please explain the expression and wha it means.
I just dont understand what it means
thanks!
DS OG #142
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Statement (2) reads:
x > 0
And that's it. You must have misread it?
Because (2) tells us only about x and nothing about b, it must be insufficient given the question.
Rey
x > 0
And that's it. You must have misread it?
Because (2) tells us only about x and nothing about b, it must be insufficient given the question.
Rey
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My version of the OG has:rey.fernandez wrote:Statement (2) reads:
x > 0
And that's it. You must have misread it?
Because (2) tells us only about x and nothing about b, it must be insufficient given the question.
Rey
(2) x > 0 = b
in both the question and the explanation section. However, the actual explanation ignores the info.
I'd just write this off as a really bad question.
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