expanding triple brackets i will give brainliest!

Answer:
[tex]x^{3} -13x^{} -12[/tex]
Step-by-step explanation:
(x+1) (x−4) (x+3)
= ((x+1)(x−4)) (x+3)
= ((x+1)(x−4)) (x)+((x+1)(x−4)) (3)
= [tex]x^{3} -3x^{2} -4x^{} +3x^{2} -9x^{} -12[/tex]
= [tex]x^{3} -13x^{} -12[/tex]