![y(x)=\frac{x-1}{x}=\frac{x}{x}-\frac{1}{x}=1-x^{-1}\\\\ y'(x)=[1-x^{-1}]'=[1]'-[x^{-1}]'=0-(-1)*x^{-1-1}=x^{-2}=\frac{1}{x^2}\\\\ (\frac{u}{v})=\frac{u'*v-u*v'}{v^2}\\\\ y'(x)=[\frac{x-1}{x}]'=\frac{[x-1]'*x-(x-1)*[x]'}{x^2}=\\\\ =\frac{[(x)'-(1)']*x-(x-1)*[1]}{x^2}=\frac{[1-0]*x-(x-1)}{x^2}=\\\\ =\frac{x-x+1}{x^2}=\frac{1}{x^2}](/tpl/images/0902/8149/c584c.png)
1) D=9-4*4*(-2)=25
x=(3+-5)/4
x1=2
x2=-0.5
2(x+0.5)(x-2)=(x+1)(x-2)
2) D=64-4*3*(-3)=100
x=(-8+-10)/6
x1=1/3
x2=-3
3(x-1/3)(x+3)=(x-1)(x+3)
3)D=4-4*3*(-1)=16
x=(-2+-4)/6
x1=1/3
x2=-1
3(x-1/3)(x+1)=(x-1)(x+1)
4)D=25-4*2*(-3)=1
x=(-5+-1)/4
x1=-1
x2=-3/2
2(x+3/2)(x+1)=(x+3)(x+1)
5) (2-10a)(2+10a)
6) (5xy-4)(5xy+4)
7) D=1-4*1*(-30)=121
x=(1+-11)/2
x1=6
x2=-5
(x-6)(x+5)
8)D=1-4*1*(-42)=169
x=(-1+-13)/2
x1=6
x2=-7
(x-6)(x+7)
D-это дискриминант
