How do you multiply #root3a (root3(a^2) + root3(81a^2)) #? Algebra Radicals and Geometry Connections Multiplication and Division of Radicals 1 Answer GiĆ³ Oct 2, 2015 I found: #a(1+3root3(3))# Explanation: We can multiply first: #root3(a)*root3(a^2)+root3(a)*root3(81a^2)=# and rearrange: #=root3(a*a^2)+root3(a*81a^2)=# #=root3(a^3)+root3(81a^3)=# taking cube roots: #=a+aroot3(81)=a+aroot3(27*3)==a+3aroot3(3)=# #=a(1+3root3(3))# Answer link Related questions How do you simplify #\frac{2}{\sqrt{3}}#? How do you multiply and divide radicals? How do you rationalize the denominator? What is Multiplication and Division of Radicals? How do you simplify #7/(""^3sqrt(5)#? How do you multiply #(sqrt(a) +sqrt(b))(sqrt(a)-sqrt(b))#? How do you rationalize the denominator for #\frac{2x}{\sqrt{5}x}#? Do you always have to rationalize the denominator? How do you simplify #sqrt(5)sqrt(15)#? How do you simplify #(7sqrt(13) + 2sqrt(6))(2sqrt(3)+3sqrt(6))#? See all questions in Multiplication and Division of Radicals Impact of this question 1220 views around the world You can reuse this answer Creative Commons License