2x^2+4x-5x^2+10x+3=0
-3x^2+14x+3=0
Объяснение:x²+2x=t, t²-5t+3=0 ,t1=(5+√13)/2, t2=(5-√13)/2
1)x²+2x=(5+√13)/2, x²+2x-(5+√13)/2=0,D>0, x1+x2=-2,x1·x2=-(5+√13)/2(т.Виета).
x1²+x2²=(x1+x2)²-2x1x2=4-(-2·(5+√13 /2)=4+5+√13=9+√13.
2)x²+2x=(5-√13)/2,x²+2x-((5-√13)/2)=0,D>0
x3²+x4²=(x3+x4)²-2x3x4=4-(-2·(5-√13)/2)=4+5-√13=9-√13.
x1²+x2²+x3²+x4²=18.
2x^2+4x-5x^2+10x+3=0
-3x^2+14x+3=0
Объяснение:x²+2x=t, t²-5t+3=0 ,t1=(5+√13)/2, t2=(5-√13)/2
1)x²+2x=(5+√13)/2, x²+2x-(5+√13)/2=0,D>0, x1+x2=-2,x1·x2=-(5+√13)/2(т.Виета).
x1²+x2²=(x1+x2)²-2x1x2=4-(-2·(5+√13 /2)=4+5+√13=9+√13.
2)x²+2x=(5-√13)/2,x²+2x-((5-√13)/2)=0,D>0
x3²+x4²=(x3+x4)²-2x3x4=4-(-2·(5-√13)/2)=4+5-√13=9-√13.
x1²+x2²+x3²+x4²=18.