1.196x^2-1=0 2.4x^2+12x+9=813.x^2-7x-1=0 4.2x^2+3x=35.x^2-2x+1=25

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1.196x^2-1=0 2.4x^2+12x+9=813.x^2-7x-1=0 4.2x^2+3x=35.x^2-2x+1=25

1.196x^2-1=0 2.4x^2+12x+9=813.x^2-7x-1=0 4.2x^2+3x=35.x^2-2x+1=25
1.196x^2-1=0 2.4x^2+12x+9=81
3.x^2-7x-1=0 4.2x^2+3x=3
5.x^2-2x+1=25

1.196x^2-1=0 2.4x^2+12x+9=813.x^2-7x-1=0 4.2x^2+3x=35.x^2-2x+1=25
196x²-1=0
196x²=1
x²=1/196
x=±1/14
4x²+12x+9=81
4x²+12x-72=0
x²+3x-18=0
(x+6)(x-3)=0
x1=-6 x2=3
x²-7x-1=0
b²-4ac=53
x=(7±√53)/2
2x²+3x=3
2x²+3x-3=0
b²-4ac=33
x=(-3±√33)/4
x²-2x+1=25
x²-2x-24=0
(x-6)(x+4)=0
x1=6 x2=-4

1)
196x^2=1,
x^2=1/196,
x1=1/14,x2=-1/14
2)4x^2+12x-72=0,
x^2+3x-18=0,
(x+6)(x-3)=0
x1=-6,x2=3
3)a=1,b=-7,c=-1,
判别式=49+4=53,
x1=(7+√53)/2,x2=(7-√53)/2