Given that a>1 and b>1. Is (a^x)(b^y)<1?
(1) a^(x+y) < 1
(2) b^(x+y) < 1
Given: a^(x+y) < 1 => a^x * a^y < 1
St1 could be true in the following 3 cases:
a) x<=0 & y<=0 .............. (They cannot be both zero at the same time)
-> (a^x)(b^y)<1 is TRUE
b) x<0, y>=0 & y < Abs(x), where Abs(x) means absolute value of x
-> Whether (a^x)(b^y)<1 is true or not depends on the relation between a & b.
c) y<0, x>=0 & x < Abs(y), where Abs(y) means absolute value of y
-> Whether (a^x)(b^y)<1 is true or not depends on the relation between a & b.=> NOT SUFFICIENT
By same reasoning,=> NOT SUFFICIENT
St1 & St2 Together:
Since we still donot know and cannot deduce any relation between a & b, we cannot conclude anything.=> NOT SUFFICIENTANS: E
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