Question

разложите на множители трёхчлен:
1)x^2+4x+3
3) x^2+3x-18

Answer 1

a*(x^2) + b*x + c = a*(x - x1)*(x - x2)
1) x^2 + 4x + 3 = 0
x1 = - 3
x2 = -1
x^2 + 4x + 3 = ( x +3)*(x + 1)

3) x^2 + 3x - 18 = 0
x1 = - 6
x2 = 3
 x^2 + 3x - 18 = (x - 3)*(x + 6)