Odpowiedź :
2x2 + 5x - 12 = 0
2
2x2 + 5x = 0 + 12
2x2 + 5x = 12
a) 2x2 - 8 = 0
2x2 = 0 + 8
2x2 = 8 /:2
x2 = 4
x = pierwiastek z 4
x = 2
b) 9-x2 = 0
-x2 = 0-9
-x2 = -9 /: (-1)
x2 = 9
x = pierwiastek 9
x = 3
2
2x2 + 5x = 0 + 12
2x2 + 5x = 12
a) 2x2 - 8 = 0
2x2 = 0 + 8
2x2 = 8 /:2
x2 = 4
x = pierwiastek z 4
x = 2
b) 9-x2 = 0
-x2 = 0-9
-x2 = -9 /: (-1)
x2 = 9
x = pierwiastek 9
x = 3