Question

Precizati si justificati valoarea de adevar:
a)2/3 apartine(4/5,infinit)
b)-5/6 apartine (-infinit ,-4/5)
c)-√5 apartine [-√3,infinit)

Answer 1

a) 2/3 < 4/5 pt ca
10 < 12 adevarat
deci 2/3 ∉ (4/5, ∞)

b) -5/6 < - 4/5
5/6 > 4/5
25 > 24 adevarat
-5/6 ∈ (-∞, -4/5)

c) 5 > 3
√5 > √3
-√5 < -√3
-√5 ∉ [-√3, ∞)

Answer 2

a) 2/3=0,666666...=0,(6) mai mic decat 4/5=0,8 deci fals, 2/3 nu apartine intervalului deschis (4/5, infinit)
b) -5/6 = -0,83... < -4/5= -0,8 deci adevar
c) -rad(5) < -rad(3) (-5<-3) deci fals, -rad(5) nu apartine intervalului [-rad(3), infinit)
Succes!