SOLUTION: If n>0 and x^2n=4, then what does 9(x^3n)^2-13(x^2)^2n equal?

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Question 1183526: If n>0 and x^2n=4, then what does 9(x^3n)^2-13(x^2)^2n equal?
Answer by ikleyn(52786) About Me  (Show Source):
You can put this solution on YOUR website!
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What is written in the post, can be read in several different ways, making the post ambiguous. 


I will assume that the problem is as follows.


        If n>0 and x%5E%282n%29 = 4, then find  9%28x%5E%283n%29%29%5E2 - 13%2A%28x%5E2%29%5E%282n%29.



If  x%5E%282n%29 = 4,  then  9%28x%5E%283n%29%29%5E2 = 9%2Ax%5E%286n%29 = 9%2A%28x%5E%282n%29%29%5E3 = 9%2A4%5E3 = 9*64 = 576;

                      13%2A%28x%5E2%29%5E%282n%29 = 13%2Ax%5E%284n%29 = 13%2A%28x%5E%282n%29%29%5E2%29 = 13%2A4%5E2 = 13*16 = 208.


Therefore, the answer to the problem's question is  576 - 208 = 368.