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x>5⇒ 5 <5
x +1 6
x >5⇒x >1
5
. 5 < 5 <1<x .5 x
x +1 6 5
x +1 5
.5
x +1
() .8 +c > 4 +c 8 > 4 :( ) ()
()
( ) c=0 ( ) c≤0 ()
()
.c ≥ 0 ()
:( )
1 ≤ 2x − 1 ≤ 11 ⇔ 2 ≤ 2x ≤ 12 ⇔ 1 ≤ x ≤ 6
6−1 = 5
:( )
−2.4 < x < −1.5 ⇒ −2.4p < px < −1.5p
⇒ −2.4p < px < 0
x2 − y2 :( )
.y2 x2
x 2 − y2 = (−6 )2 − 0 = 36
:( )
(x − 1)2 ≥ 0 ⇔ x 2 − 2x + 1 ≥ 0
⇔ x 2 + 1 ≥ 2x
⇔ x +1 ≥2
x