Answer: 3x^12y^10
Remove unnecessary parenthesis
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9x^8y^4*1/3x^4y^6
Reduce the numbers with greatest common divisor 3
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3x^8y^4x^4y^6
Multiply the terms with the same base by adding their exponents
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3x^8+4y^4+6
Add the numbers
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3x^12y^10
I tried my best :)
Hope this helps!