Question

Aflati x apartine nr naturale incat fractia 2x + 1 supra 9 sa fie subunitara , supraunitara , echivalenta

Answer 1

subunitara
(2x+1)/9 <1
2x+1<9
2x<8
x<4
x∈{-∞,4)
supraunitara
(2x+1)/9 >1
(2x+1)/9 >1
2x+1>9
2x>8
x>4
x∈(4,+∞}
echivalenta
(2x+1)/9 =1
2x+1=9
2x=8
x=4
x∈{4}