[tex]P(x)=2[(3x^2+1)(x^2+1)+(3x^2+1)(2x^2-1)+(x^2+1)(2x^2-1)]=\\2[3x^4+3x^2+x^2+1+6x^4-3x^2+2x^2-1+2x^4-x^2+2x^2-1]=\\2(11x^4 + 4x^2 - 1)[/tex]
Dziedzina:
(3x^2+1)(x^2+1)(2x^2-1)>0
2x^2-1>0 |:2
x^2-1/2>0
(x-√2/2)(x+√2/2)>0
x∈(-∞;-√2/2)∪(√2/2;+∞)
