x/2+x-2/4 = x+2/9
x/2+x-х = 2/9+2/4
x/2 = 2/9+2/4
(x+18)/36 = (2+4)/36+(2+9)/36
(x+18)/36 = 6/36+11/36
(x+18)/36 = 17/36
x/36+18/36 = 17/36
x/36 = 17/36-18/36
x/36 = -1/36
<u><em>х=13/9</em></u>
или
2 способ на фото
ответ тот же
1) ( a - 12)^3 - 5^3 = ( a - 12 - 5)(a^2-24a+144+5a-60+25)=(a-17)(a^2-19a+109)
2) ( b + 4)^3 + 4^3 = (b + 4 + 4)(b^2+8b+16 -4b-16+16) =(b + 8)(b^2+4b+16)
3) ( x^2 + 1)^2 - 4x^2 = ( x^2 + 1 - 2x)(x^2 + 1 + 2x)=(x^2-2x+1)(x^2+2x+1)=
= (x - 1)(x- 1)(x+ 1)(x+ 1)
4) (y^2 + 2y)^2 - 1 = (y^2 + 2y - 1)(y^2 + 2y + 1) = (y + 2y - 1)(y + 1)(y + 1)
5) ( 9 - c^2 - 6c)(9 + c^2 + 6c)=( - c^2 - 6c + 9)(c^2 + 6c + 9)
6) (4m - m+ n)(4m + m - n)= (3m + n)(5m - n)
3. 1.
(a⁰,⁵-a¹,⁵)/(1-a)=a⁰,⁵*(1-a⁽¹,⁵⁻⁰,⁵⁾)/(1-a)=a⁰,⁵*(1-a)/(1-a)=a⁰,⁵.
(3x - y)(2y - 7x) = 6xy - 21x² - 2y² + 7xy = 13xy - 21x² - 2y²