1) 3X^2 + 2X - 1 = ( X + 1)*(X - 1\3)
D = 4 - 4*3*(-1) = 16 ( V D = 4)
X1 = ( - 2 + 4 ) \ 6 = 2\6 = 1\3
X2 = - 6 \ 6 = - 1
2) 4X + 4 = 4*(X +1)
3) вся дробь после сокращения: 4 \ ( Х - 1\3) - ( ОТВЕТ )
Х² + 7х + 6 = 0
х1 + x2= -7
х1 × х2 = 6
х1 = -1
х2 = -6
х² + х = 56
х² + х - 56 = 0
х1 + х2 = -1
х1 × х2 = -56
х1 = -8
х2 = 7
3х² + 5х - 2 = 0
D = 25 - 4 × 3 × (-2) = √49 = 7
x1 = -5 + 7 / 2 × 3 = 2 / 6 = 1 / 3
x2 = -5 - 7 / 2 × 3 = -12 / 6 = -2
Формула :
a^2-b^2 = (a-b)(a+b)