Answer:
[tex]-4x^{4} + x^{2} + 6[/tex]
Step-by-step explanation:
[tex](-4x^{4} + 6x^{2} + 3) - (5x^{2} - 3) = -4x^{4} + 6x^{2} + 3 - 5x^{2} + 3 = -4x^{4} + 6x^{2} - 5x^{2} + 3 + 3 = -4x^{4} + x^{2} + 6[/tex]
