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Thank you. Yes, i must find what it equals to (I know already is 3 from the answers) but i don't know how to solve it.

Homework Statement order 3 radical from (9+4radical5) + order 3 radical from (9-4radical5) *note: 9+4radical5 is all under the big order 3 radical. (so is the other one) Homework Equations in case you don't understand what i wrote (sorry, my language is not english and math linguistics...