Answer:
Third option is the correct answer
Step-by-step explanation:
[tex]3 {x}^{5} \bigg( 2 {x}^{2} + 4x + 1 \bigg) \\ \\ = 3 {x}^{5} \times 2 {x}^{2} + 3 {x}^{5} \times 4x + 3 {x}^{5} \times 1 \\ \\ = 3 \times 2 {x}^{5 + 2} + 3 \times 4 {x}^{5 + 1} + (3 \times 1) {x}^{5} \\ \\ \red{ \bold{= 6{x}^{7} + 12{x}^{6} +3 {x}^{5} }}[/tex]
