Question

Rezolvati in multimea numerelor naturale inecuatiile:
a) (x+2)(3x-5)-12≤(x+1)(3x-7)
b)(x-2)(2x+5)-9≤(2x+5)(x-3)
c)(x-7)(x+7)-(x-5)²≤x-2
AJUTOOORRR VAA rogg

Answer 1

a) (x+2)(3x-5)-12≤(x+1)(3x-7)
3x²+6x-5x-10-12≤3x²+3x-7x-7
x-22≤-4x-7
4x+7+x-22≤0
5x-15≤0
x≤3

b)(x-2)(2x+5)-9≤(2x+5)(x-3)
2x²-4x+5x-10-9≤2x²+5x-6x-15
x-19≤-x-15
2x≤4
x≤2

c)(x-7)(x+7)-(x-5)²≤x-2
x²-49-x²+10x-25≤x-2
10x-74≤x-2
9x≤72
x≤8