3x^2 + 13x - 10 = 0
D = b^2 - 4ac = 13^2 + 4*10*3 = 289 = 17^2
x1 = ( - 13 + 17)/6 = 4/6 = 2/3
x2 = ( - 13 - 17)/6 = - 30/6 = - 5
Объяснение:
(х^3 -7)/(1-х) -6/(х-1)=(х^3 -7+6)/(1-х)=(х^3 -1)/(1-х)=-(х-1)(х^2 +х+1)/(х-1)=-х^2 -х-1
( Х - 1 )/5 = ( 5 - Х )/2 + ( 3х/4 )
<span>4( Х - 1 ) = 10( 5 - Х ) + 15х </span>
<span>4х - 4 = 50 - 10х + 15х </span>
<span>4х - 4 = 50 + 5х </span>
<span>5х - 4х = - 4 - 50 </span>
<span>Х = - 54</span>
5х²-6х+1=0 Д=b²-4ac= 36-4*5*1= 36-20=16
D>0, два корня
Х1= 6+4/2=5
Х2=6-4/2=1
Ответ: 1;5
2) х(х+1)=56
Х²+х-56=0
Д= 1-4*1*(-56)= 1+224=225
Х1= 1+15/2=16/2=4
Х2=1-15/2=-14/2=-7
Ответ: -7;4