D=100–84=16
x=(10+4)/2=7; x=(10–4)/2=3
x2–10x+21=(x–7)(x–3)
Неравенство принимает вид:
(4х+7)2(x–7)/(x–3)(x–7) ≥ (4x–7)2/(x–3)(x–7)
или
(4x–7)2(x–7–1)/(x–3)(x–7)≥ 0
(4x–7)2(x–8)/(x–3)(x–7)≥ 0
Решаем методом интервалов:
___–___[7/4]_–__ (3) _+__ (7) __–__[8]_+_