Answer:
1 Remove parentheses.
{x}^{4}(3{x}^{2}-2)(4{x}^{2}+5x)x
4
(3x
2
−2)(4x
2
+5x)
2 Expand by distributing terms.
(3{x}^{6}-2{x}^{4})(4{x}^{2}+5x)(3x
6
−2x
4
)(4x
2
+5x)
3 Use the FOIL method: (a+b)(c+d)=ac+ad+bc+bd(a+b)(c+d)=ac+ad+bc+bd.
12{x}^{8}+15{x}^{7}-8{x}^{6}-10{x}^{5}12x
8
+15x
7
−8x
6
−10x
5
