surendar26 wrote:
If Z>-8,Z may be any value b/t -7 to infinity then -2<Z<8 condition will fail.
We are told that \(-2<z<8\), so
this statement is GIVEN to be true. For example z might be -1, 0, 1.5, 5, ... ANY value of z from this (true) range \(-2<z<8\) will be more than -8.
So when you say that z might for example be -7 it's not true as \(-2<z<8\).
To elaborate more. Question uses the same logic as in the examples below:If \(x=5\), then which of the following must be true about \(x\):A. x=3
B. x^2=10
C. x<4
D. |x|=1
E. x>-10
Answer is E (x>-10), because as x=5 then it's more than -10.
Or:
If \(-1<x<10\), then which of the following must be true about \(x\):A. x=3
B. x^2=10
C. x<4
D. |x|=1
E. x<120
Again answer is E, because ANY \(x\) from \(-1<x<10\) will be less than 120 so it's always true about the number from this range to say that it's less than 120.
Or:
If \(-1<x<0\) or \(x>1\), then which of the following must be true about \(x\):A. x>1
B. x>-1
C. |x|<1
D. |x|=1
E. |x|^2>1
As \(-1<x<0\) or \(x>1\) then ANY \(x\) from these ranges would satisfy \(x>-1\). So B is always true.
Hope it's clear.