Question

Rezolvați in mulțimea nr. întregi inecuatia:
(x+1) la puterea a 2 - (x-2) la puterea a 2 >4-x

Answer 1

x²+2x+1-(x²-4x+4)>4-x
x²+2x+1-x²+4x-4>4-x
6x-3>4-x
7x>7, x>1, x∈(1,+∞)

Answer 2

(x+1)²- (x-2)² > 4-x
x²+2x+1-x²+4x-4-4+x > 0
7x-7> 0
7x>  7
x> 1

S={2..+∞}