2. (а-3)(а+3) = а^2 - 3^2 = а^2 - 9;
(2у+5)(2у-5) = (2у)^2 - 5^2 = 4y^2 - 25;
3. (6x-x^2)^2-x^2(x-1)(x+1)+6x(3+2x^2) = 36x^2 - x^4 - x^4 + x^2 + 18x + 12x^3 = 37x^2 - 2x^4 + 18x + 12x^3
3. (x-4)(x^2 + 4x + 16) = x^3 - 4x^2 + 4x^2 - 16x + 16x - 64 = x^3 - 64 = (x-64)(x^2 - 4x + 16)
![\frac{x^2+3x-10}{x^2+11x+30} \leq 0 \\ \\ x^2+3x-10=0 \\ x1=-5 \\ x2=2 \\ \\ x^2+11x+30=0 \\ x1=-5 \\ x2=-6 \\ \\ \frac{(x-2)(x+5)}{(x+5)(x+6)} = \frac{x-2}{x+6} \leq 0 \\ \\ x \neq -5 \\ x \neq -6](https://tex.z-dn.net/?f=+%5Cfrac%7Bx%5E2%2B3x-10%7D%7Bx%5E2%2B11x%2B30%7D++%5Cleq+0+%5C%5C+%5C%5C+x%5E2%2B3x-10%3D0+%5C%5C+x1%3D-5+%5C%5C+x2%3D2+%5C%5C+%5C%5C+x%5E2%2B11x%2B30%3D0+%5C%5C+x1%3D-5+%5C%5C+x2%3D-6+%5C%5C+%5C%5C+%5Cfrac%7B%28x-2%29%28x%2B5%29%7D%7B%28x%2B5%29%28x%2B6%29%7D+%3D+%5Cfrac%7Bx-2%7D%7Bx%2B6%7D+%5Cleq+0+%5C%5C+%5C%5C+x+%5Cneq+-5+%5C%5C+x+%5Cneq+-6+)
+ _ +
.......-6.//////////2........
Ответ:х=(-6;2].
-2^3/(-2+1/3)+1/3=-8/(-2)+(-8/1/3)=4-8*3/1=4-24=-20
Помоему 4) точно правда не знаю..подожди других