Respuesta :

Answer:

8(X^2+1)

Step-by-step explanation:

(X²+3)²-(X²-1)

(X²+3)(X²+3)-(X²-1)(X²-1)

X⁴+3X²+3X²+9-(X⁴-X²-X²+1)

X⁴+6X²+9-(X⁴-2X²+1)

X⁴+6X²+9-X⁴+2X²-1

8X²+8

good job