Respuesta:
1. D
2. C
3. A
[tex]a = \frac{(4 {x}^{2} + 5x + 1) +( 6 {x}^{2} + 7x - 5) }{2} (8x + 6) \\ \\ a = \frac{10x {}^{2} + 12x - 4}{2} (8x + 6) \\ a =(5 {x}^{2} + 6x - 2)(8x + 6) \\ a = 40 {x}^{3} + 48x {}^{2} - 16x + 36 {x} - 12 \\ a = 40 {x}^{3} + 48 {x}^{2} + 20x - 12[/tex]
