Ответы и объяснения

2013-04-28T13:00:36+00:00

1). нет решений
3 x^2 - 8x + 6 = 0
D = 64 - 4 * 3 * 6 < 0
2). x  = корень 0,04
x= +- 0,2
3) x( x+3) = 0
x = 0 или x = -3
4) 7x^2 + 4x - 3 = 0
D = 16 - 4 * 7 * (-3) = 100
x1 = -4+10 / 2*7 = 3 / 7
x2 = -4-10 / 2*7 = -1
5). 4x^ 2 - 20x+ 25 = 0 
D = 400 - 4*4*25 = 0
x = 20 / 2* 4 = 2,5
6). x^2 -6x - 16 = 0
D = 36 - 4* (-16) = 100
x1 = 6 +10 / 2 = 8
x2 = 6 - 10/ 2 = -2
7). - 6m^2 + 19m - 10 = 0
D = 361 - 4*(-6) *(-10) = 121
x1 = -19 -11/ 2*(-6) = 2,5
x 2 = -19+11/ 2*(-6) = 2/3