(1/5с * 1/10с) * 2с²/3с = 1/50с² * 2с²/3с = 1/75с
![\overline {a}=(1,-2,m)\; ,\; \overline{b}=(n,6,3)\\\\\overline {a}||\overline {b}\; \to \; \frac{1}{n}=\frac{-2}{6}=\frac{m}{3}\\\\n=\frac{6}{-2}=-3\\\\m=\frac{-2\cdot 3}{6}=-1\\\\|\overline {b}|=3|\overline{a}|\; ,\; \overline {b}=-3\overline {a}](https://tex.z-dn.net/?f=%5Coverline+%7Ba%7D%3D%281%2C-2%2Cm%29%5C%3B+%2C%5C%3B+%5Coverline%7Bb%7D%3D%28n%2C6%2C3%29%5C%5C%5C%5C%5Coverline+%7Ba%7D%7C%7C%5Coverline+%7Bb%7D%5C%3B+%5Cto+%5C%3B+%5Cfrac%7B1%7D%7Bn%7D%3D%5Cfrac%7B-2%7D%7B6%7D%3D%5Cfrac%7Bm%7D%7B3%7D%5C%5C%5C%5Cn%3D%5Cfrac%7B6%7D%7B-2%7D%3D-3%5C%5C%5C%5Cm%3D%5Cfrac%7B-2%5Ccdot+3%7D%7B6%7D%3D-1%5C%5C%5C%5C%7C%5Coverline+%7Bb%7D%7C%3D3%7C%5Coverline%7Ba%7D%7C%5C%3B+%2C%5C%3B+%5Coverline+%7Bb%7D%3D-3%5Coverline+%7Ba%7D)
Векторы противоположнонаправлены и вектор в в 3 раза длиннее вектора а.
(3(2x+1)^2 +4(2x+5)^2) /(2x+5)^2*(2x+1)^2 =7/(2x+5)(2x+1)
(3(4x^2+4x+1)+4(4x^2+20x+25)) /(2x+5)^2*(2x+1)^2 =7/(2x+5)(2x+1)
(12x^2+12x+3+16x^2+80x+100)/(2x+5)^2*(2x+1)^2 =7/(2x+5)(2x+1)
(28x^2+92x+103)/(2x+5)^2*(2x+1)^2 -7/(2x+5)(2x+1) =0
(28x^2+92x+103 -7(2x+5)(2x+1)) /(2x+5)^2*(2x+1)^2 =0
28x^2+92x+103 -7(4x^2 + 12x+5) =0
28x^2+92x+103 -28x^2 -84x -35 =0
8x +68 =0
8x = -68
x = -68 : 8
x = -8.5
Y(x)=ax+b
y(-2)=a*(-2)+b=3
y(2)=a*2+b=5
Складываем два этих уравнения:
2b=8
b=4
a*2+4=5
a=0.5
Ответ: y(x)=0.5x+4
1
x²-2x+1=2x²-2x+1
x²=0
x=0
2
x²+3^x+5>x²+9^x-3^x
9^x-2*3^x<0
3^X*(3^x-2)<0
3^x=0 3^x=2
0<3^x<2
x∈(-∞;log(3)2)
3
x²+2<3x
x²-3x+2<0
x1+x2=3 U x1*x2=2
x1=1 U x2=2
x∈(1;2)