1. (х+7)(17-х)<0<br>2. х^2+21х≥0
x(x+21)<=0<br>3. 6x^2-5x-4≤0
x=1/12(5+-√25+96)=(5+-11)/12
x1=16/12=4/3
x2=-1/2
6(x+1/2)(x-4/3)<=0<br>(2x+1)(3x-4)<=0<br>решаем методом интервалов
1. __<0___-7_______>0_________17______<0_______<br> (∞;-7) U (17;∞)
2. ____>0___-21____<0_____0____>0_____
(∞;-21] U [0;∞)
3. ______>0_____-1/2______<0_______4/3_____>0________
[-1/2;4/3]