Помогите с алгеброй!
Ответ:
а) x^2=49
x= 24.5
б) 8x^2-12=0
8x^2=12
x^2=12-8
x=2
в) x^2-x-2=0 a=1 b= -1 c= -2
D= (-1)^2-4*1*-2=1+8=9
x1= 1-√9/2*1=2/2=1
x2= 1+√9/2*1= 4/2=2
г)x^2-2x-3-0 a=1 b= -2 c= -3
D= (-2)^2-4*1*-3=4+12=16
x1= 2-√16/2*1=2/2=2
x2= 2+√16/2*1=6/2=3
а) = 49
x = 7 и x = -7
б) 8 -12 = 0
8( - 1,5) = 0
= 1,5
x = и x = -
в) - x - 2 = 0
Д = 1+8 = 9
x1 = = 2
x2 = = - 1
г) - 2x - 3 = 0
Д = 4+12 = 16
x1 = = 3