Разложить кв трехчлен(через дескреминант) {x}-степень 3x{2}+0.9x-2.1=0 a=3 b=0.9 c=-2.1 D=b{2}-4ac D=
D= 0.9^2-4*3*(-2.1)=0.81+25.2=26.01=5.1
x1=-0.9+5.1/6=0.7
x2=-0.9-5.1/6=-1
3x^2+0.9x-2.1=(x-0.7)(x+1)
3*x*2+0.9*x-2.1 = 0*a , 0*a = 3*b , 3*b = 0.9*c , 0.9*c = - 2.1*d , - 2.1*d = b*2-4*a*c
6.9x - 2.1 = 0.0 = 3b, 3b = 0.9c, 0.9c = - 2.1d, -2.1d = 2b - 4ac
23x = 7
a = r, b = 0, c = 0, d = 0, x = 0.304347826086957; r ∈ R