Question

Choose the correct simplification of 9x2(4x + 2x2 − 1).

18x4 + 36x3 − 9x2
18x4 − 36x3 + 9x2
36x4 + 18x3 − 9x2
36x4 − 13x3 + 9x2

Answer 1

first one 18x4 + 36x3 - 9x2

Answer 2

`18x^(4)+36x^(3) -9x^{2`

Explanation:

Hello

For this operation, the monomial must be multiplied by each of the monomials that form the polynomial

so, we have

by definition

`(a*x^(n)) *(b*x^(m) )=ab*x^(n+m)`

`9x^(2) (4x+2x^(2) -1)=(9x^(2) *4x)+(9x^(2))(2x^(2) )-9x^(2)*(1)\\                                 =36x^(3) +18x^(4) -9x^(2) \\\\now,\ organizing\ the\ terms\\\\\\9x^(2) (4x+2x^(2) -1)=18x^(4)+36x^(3) -9x^(2)`

the answer you are searching for is

`18x^(4)+36x^(3) -9x^(2)`

Have a great day