А) <span>f </span>⁾<span>(x)= 3x^2 + x - 4
D=1+48=49
x=(-1+7)/6=1
x=(-1-7)/6= -4/3
+ - +
---------- -4/3---------1--------------------
x</span>∈(-∞;-4/3)∪(1;+∞)
б) <span>f(x)= 2x + x^2/2 - x^3/3
</span><span>f</span>⁾<span>(x)= 2+х-х</span>²
D=1+8=9
x=(-1+3)/(-2)=-1
x=(-1-3)/(-2)=2
- + -
__________ -1________2________
x∈(-1; 2)
Ответ:
1. -2х+8 и - 2х+8 не равны
2. 3а+3 и 3а-11 не равны
(3x²-xy)/(9x²-6xy+y²)=(x(3x-y))/(3x-y)²=x/(3x-y)=(3/4)/(3*(3/4)-(-2/3))=(3/4)/(35/12)=9/35