a)x²-3x-4=x²-4x+x-4=x(x-4)+(x-4)=(x-4)(x+1)
⇒inecuatia devine:(x-4)(x+1)/x(4-x)≥0⇔(-x-1)/x≥0⇒-x-1≥0⇒x≤-1⇒x∈(-∞,-1]
b)(x-3)/(x+1)≥(2x-5)/(x+2)⇔(x-3)(x+2)≥(x+1)(2x-5)⇔x²+2x-3x-6≥2x²-x+2x-5
x²+2x+1≤0⇔(x+1)²≤o⇒x≤-1⇒x∈(-∞,-1]
c)x²-5x+6=x²-3x-2x_6=x(x-3)-2(x-3)=(x-3)(x-2)
⇒inec.devine:(x-3)/(x-4)>(x-3)(x-4)/(x-2)⇔1>x-3⇒x<4⇒x∈(-∞,4)
d)
