1) x^{2} +6х+5=0 2) x^{2} -1.8х-3.6=0 3) 4x^{2} - вопрос №56850291265022183603421404223052 от nosok666 25.11.2020 22:18

Question

Алгебра: 1) x^{2} +6х+5=0 2) x^{2} -1.8х-3.6=0 3) 4x^{2} -х-14=0 4) 2 x^{2}+х-3=0 5) 2 x^{2}-9х=35

nosok666 · Answer

Х²+6х+5=0а=1 , b=6 , с=5D= b²-4ac  D= 36 -4*1*5 =36-20= 16D 0 два корня уравнения , √D= 4х₁, х₂ = (-b +- √D) /2ax₁= (-6-4)/2 =-10/2=-5x₂= (-6+4)/2 = -2/2=-1x² -1.8x -3.6 =0D= (-1.8)² - 4* 1* (-3.6) = 3.24 +14.4 = 17.64D 0  ,  √D= 4.2х₁= (1,8 - 4,2 ) / 2 =  2,4/2=1,2х₂= (1,8+4,2)/2 = 34х²-х-14=0D= (-1)² -4 *4 *(-14)=1+ 224=225D 0 , √D= 15x₁= (1-15)/(2*4)= 14/8= 1.75x₂= (1+15)/8= 16/8=22x²+x-3=0D= 1 -4*2*(-3) = 1+24=25D 0 , √D= 5x₁= (-1-5) /(2*2) = -6/4= -1.5x₂= (-1+5)/4 =12x²-9x=352x²-9x-35 =0D=...