Question

помогите пожалуйста 12x^2-21x+9=0

Answer 1

12x²-21x+9=0
D = 21² - 4 * 12 * 9
D = 441 - 432
D = 9 = 3²
x1 = (21 + 3) : (12 * 2) = 24 : 24 = 1
x2 = (21 - 3) : (12 * 2) = 19 : 24 = 0.75
Ответ: x1 =1      и   x2 = 0.75

Answer 2

12x^2 - 21x + 9 = 0
4x^3 - 7x + 3 = 0
D = b^2 - 4ac = 49 - 48 = 1
x1 = ( 7 + 1) / 8 = 1
x2 = ( 7 - 1) / 8 = 0,75