Решите: 5x^2-9x+4<=0<br>
5x²-9x+4≤0 5x²-9x+4=0 D=81-4*5*4=81-80=1 x₁=9-1 = 0.8 10 x₂=9+1=1 10 + - + --------- 0.8 ------------ 1 ------------- \\\\\\\\\\\\\ x∈[0.8; 1]