Answer:
[tex]4 {n}^{5} + 3.5 {n}^{5} + ( - 2.1 {n}^{5} )[/tex]
first create a bracket:
[tex] = ( {4n}^{5} + 3.5 {n}^{5} ) + ( - 2.1 {n}^{5} )[/tex]
then solve the first bracket:
[tex] = {7.5 {n}^{5} } + ( - 2.1 {n}^{5} )[/tex]
then open the remaining bracket:
[tex] = {7.5n}^{5} - {2.1n}^{5} [/tex]
carryout the subtraction operation:
[tex] = (7.5 - 2.1) {n}^{5} \\ { \boxed{ = {5.4n}^{5} }}[/tex]
