![\sqrt{x} 6-x сокращается](https://tex.z-dn.net/?f=+%5Csqrt%7Bx%7D+6-x+%D1%81%D0%BE%D0%BA%D1%80%D0%B0%D1%89%D0%B0%D0%B5%D1%82%D1%81%D1%8F)
и получается уравнение:
![x^{2}](https://tex.z-dn.net/?f=++x%5E%7B2%7D+)
-6x-7=0
![x^{2}](https://tex.z-dn.net/?f=+x%5E%7B2%7D+)
-7x+x-7=0
x(x-7)+1(x-7)=0
(x-7)(x+1)=0
x=7 и х=-1
(a+b)b-(a^2+b^2)(a-2)=ab+b²-a³+2a²-ab²+2b³
B10 = b1*q^9
b8 = b1*q^7
b10/b8 = b1*q^9/<span>b1*q^7 = q^2 = 9 => q = 3
b3 = b1*q^2
b6 = b1*q^5
b3 + b6 = </span>b1*q^2 + <span>b1*q^5 = b1(q^2 + q^5) = 168 => b1 = 168 / (q^2 +q^5) =
=168 / (3^2 + 3^5) = 168 / (9 + 243) = 168 / 252 = 2/3</span>