Let R(x)=3x^3+2x^2+x and S(x)=4+1. Find R(x) * S(x)
Pls help!!!!

3x^3 x 4x^2 = 12x^5
3x^3 x 1 = 3x^3
2x^2 x 4x^2 = 8x^4
2x^2 x 1 = 2x^2
1x x 4x^2 = 4x^3
1x x 1 = 1x
12x^5 + 3x^3 + 8x^4 + 2x^2 + 4x^3 + 1x
Simplify
12x^5 + 7x^3 + 8x^4 + 2x^2 + 1x
Thus, answer is B
Hope this helps!