Hallo anonymous!
solve 3x^2-8x-11=0
3 x² - 8 x - 11 = 0 [ / 3
x² (- 8 / 3) x (- 11 / 3) = 0
p = - 8 / 3 q = - 11 / 3
x(1;2) = - p / 2 ±√ ((p / 2)² - q)
x(1;2) = 4 / 3 ±√ ((4 / 3)² + 11 / 3)
x(1;2) = 4 / 3 ±√ (16 / 9 + 33 / 9) = 4 / 3 ±√ (49 /9) = 4 / 3 ± 7 / 3
x1 = 11/3 = 3 2/3
x2 = - 3/3 = - 1
x1 = 3 2/3
x2 = - 1
test:
3 x² - 8 x - 11 = 0
3*(11/3)²-8*(11/3)-11=0
0=0 okey
3*(-1)²-8*(-1)-11=0
0=0 okey
:- )
Hallo anonymous!
solve 3x^2-8x-11=0
3 x² - 8 x - 11 = 0 [ / 3
x² (- 8 / 3) x (- 11 / 3) = 0
p = - 8 / 3 q = - 11 / 3
x(1;2) = - p / 2 ±√ ((p / 2)² - q)
x(1;2) = 4 / 3 ±√ ((4 / 3)² + 11 / 3)
x(1;2) = 4 / 3 ±√ (16 / 9 + 33 / 9) = 4 / 3 ±√ (49 /9) = 4 / 3 ± 7 / 3
x1 = 11/3 = 3 2/3
x2 = - 3/3 = - 1
x1 = 3 2/3
x2 = - 1
test:
3 x² - 8 x - 11 = 0
3*(11/3)²-8*(11/3)-11=0
0=0 okey
3*(-1)²-8*(-1)-11=0
0=0 okey
:- )