(2-X)(2+X)(4+X^2)+(6-X^2)^2
если х= -1/2

(2-X)(2+X)(4+X^2)+(6-X^2)^2 = (4-х²)(4+х²) + (6-х²)² = 16 - х⁴ +36 - 12х² + х⁴ = -12х² + 52 = -12(-1/2)² + 52 = -3 +52 = 49