Question

What is the answer to the problem rmula1" title="(x {3})^{3} = x^n" alt="(x {3})^{3} = x^n" align="absmiddle" class="latex-formula">

Answer 1

Solve for x:
x^9 = n x

Subtract n x from both sides:
x^9 - n x = 0

Factor x and constant terms from the left hand side:
-x (n - x^8) = 0

Multiply both sides by -1:
x (n - x^8) = 0

Split into two equations:
x = 0 or n - x^8 = 0

Subtract n from both sides:
x = 0 or -x^8 = -n

Multiply both sides by -1:
x = 0 or x^8 = n

Taking 8^th roots gives n^(1/8) times the 8^th roots of unity:
Answer: x = 0 or x = -n^(1/8) or x = -i n^(1/8) or x = i n^(1/8) or x = n^(1/8) or x = -(-1)^(1/4) n^(1/8) or x = (-1)^(1/4) n^(1/8) or x = -(-1)^(3/4) n^(1/8) or x = (-1)^(3/4) n^(1/8)