Pre-Calculus radical help (Im desperate need answer quickly!)

Ok, so i have literally done this question like 5 or 6 times, and i am at my wits end. I've gotten two different answers, nether of which are correct. so heres the question:

So i know this looks weird but my computer can only show so much. so • means multiply, and all the square roots (√) are to the root 4 (as in (^4>)√32 = 2√2

5(^4>)√32+2(^4>)√8•(^4>)√4
(would be written out 5 fourth root, with 32 inside, etc)
The math book says the answer is 14(^4>)√2

im like 90% sure that this isnt possible because you can't simplify (^4>)√4? nothing times itself 4 times equals 4. Am i wrong, is the book wrong? And if so, what is the answer?

Thanks for any help you can give!
-TIFT

I'll use the notation x^(1/4) for the fourth root of x.

5*32^(1/4) + 2*8^(1/4)*4^(1/4) =

5*32^(1/4) + 2*32^(1/4) =

7*32^(1/4) = 7*16^(1/4)*2^(1/4) = 7*2*2^(1/4) = 14*2^(1/4),

so I agree with the book. :)

You're welcome. I don't think it was a "stupid" mistake;
now you know what to look out for. :)

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