WoundedTiger wrote:
Is 5^n < 0.04?
(1) (1/5)^n > 25
(2) n^3 < n^2
Notice that for \(n\geq{0}\) so RHS of the Q stem is always greater than zero so we need to confirm whether n<-2 because\(5^{-2}\) is 1/25 =0.04
St 1 says (1/5)^n > 25 or n>2 so st 1 is sufficient as n is positiveSt 2 says n^3<n^2 or n(n^2-1)<0 or n(n-1)(n+1) <0Key points are n=0,-1 and 1
So we have 4 range
Case 1: n<-1 The expression n(n-1)(n+1) <0 is true
Case 2: -1<n<0, The expression is is false as it will be >0
Case3 : 0<n<1, The expression will be true
and Case 4: n>1 The expression will be true for all values
Since, we have 2 ranges in which expression holds true and for those range n <-2 or n>-2..
Ans is A[/quote]
I think red part is wrong as It should be n<-2 for statement 1
For statement 2 it comes down to n^3-n^2<0----> n^2(n-1)<0 SO for sure n-1<0 as n^2 can't be less than 0 which becomes n<1 excluding n=0, with this we can't be sure is n<-2 always.
Correct me if I am Wrong