Д) 3x^2 + 2x + 1 = 0
D=2^2 - 4 * 3 * 1 = -8
нет решение
е) x^2 - 5x / 2 - 3 = 0
x^2 - 5x - 6 = 0
D=(-5)^2 - 4 * (-6) = 25+24 = 49 = 7^2
x1= 5-7/2 = -2/2=-1
x2= 5+7/2 = 12/2=6
x1= -1
x2=6
x^4 - 29x^2 + 100 = 0
x^2=t
t^2 - 29t + 100 = 0
D=(-29)^2 - 4 *100 = 841 - 400 = 441 = 21^2
x1= 29-21/2 = 8/2 = 4
x2= 29+21/2 = 50/2 = 25
x1= 4
x2 = 25