Общий знаменатель ( Х - 2)^2= X^2 - 4X + 4 ; X ≠ 2
1 - ( X - 2 ) - 6 * ( X^2 - 4X + 4 ) = 0
1 - X + 2 - 6X^2 + 24X - 24 = 0
- 6X^2 + 23X - 21 = 0
6X^2 - 23X + 21 = 0
D = 529 - 504 = 25 ; √ D = 5
X1 = ( 23 + 5 ) : 12 = 28/12 = 2 ( 4/12 ) = 2 ( 1/3 )
X2 = ( 23 - 5 ) : 12 = 18/12 = 1,5
ОТВЕТ 2 ( 1/3 ) и 1,5
Sin(2arccos1/4)=2sin(arccos1/4)cos(arccos1/4)=2sqrt(1-1/16)*1/4=2sqrt(15)/16*1/4=sqrt(15)32
(5a+0.4)^2=25a^2+4a+1.6
(2x-1)(4x^2+2x+1)=2x^3+2x^2+2x-4x^2-2x-1=2x^3-2x^2-1