Ax^2+bx^2+ax-cx^2+bx-cx=(a+b+c)(x^2-x)
- 3 (2x + 1)(5x - 4) > 0 /:(-3)
(2x + 1)(5x - 4) < 0
2x + 1 = 0
2x = - 1
x = - 0,5
5x - 4 = 0
5x = 4
x = 0,8
+ - +
-------------- - 0, 5 ------------------ 0, 8 ---------------> x
x ∈ ( - 0,5; 0,8)
V11 - 6V2 + V2 = V11 - 6*6*2 + V2 = V11 - V72 + V2 = V63