(1) Find the range of real number k when p crosses Q= empty set.
(2) Find the value range of real number k when p crosses q = \ q ..
note:
= \ means "not equal to"
(a), when p across Q= empty set, can be divided into the following situations.
( 1)、k+ 1 & gt; 5->; K> iv
(2)、2k- 1 & lt; 4->; k & lt(5/2)
(3) Q itself is an empty set, that is, k+1>; 2k- 1->; k & lt2
To sum up, the range of real number k is {k | k>4 or k < (5/2)}.
(2),
Suppose p crosses q = q
so 4 < = k+ 1 & lt; = 5->; 3 & lt= k & lt=4
And 4
Or q itself is an empty set, that is, k+1>; 2k- 1->; k & lt2
When p crosses q = \ q
The range of real number k is {k | k >;; =2 and k=\3}