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Math question help please

Write 3^n/9^n-1 as a power of 3. Please help me with this thanks.
Original post by 2939HIHI
Write 3^n/9^n-1 as a power of 3. Please help me with this thanks.

Do you mean (3^n)/(9^(n-1))? Because 3^n/9^n-1 means 3^(n/9^n) -1, which doesn't look nice and I would heat to try to write it to the power of 3.

If you mean the former, the denominator is
9^(n-1). As a power of 3, it's 3^(2(n-1)).

You should be able to use the indices rules to solve the rest.
Reply 2
In the answer I keep getting 3^-2-n but it should be 2-n how do I turn the negative 2 to positive
Reply 3
Original post by MindMax2000
Do you mean (3^n)/(9^(n-1))? Because 3^n/9^n-1 means 3^(n/9^n) -1, which doesn't look nice and I would heat to try to write it to the power of 3.

If you mean the former, the denominator is
9^(n-1). As a power of 3, it's 3^(2(n-1)).

You should be able to use the indices rules to solve the rest.

This is what I mean (3^n)/(9^(n-1)) but I do not know because I get 3^-2-n but the answer says 3^2-n. How do I turn the negative 2 into positive?
Original post by 2939HIHI
This is what I mean (3^n)/(9^(n-1)) but I do not know because I get 3^-2-n but the answer says 3^2-n. How do I turn the negative 2 into positive?

I can't give you the direct answer, because it's against TSR rules, and there will be someone on my case against it (which is fair to be honest).

I can give you the following though
y/(x^2) = y*x^(-2)
Reply 5
Original post by MindMax2000
I can't give you the direct answer, because it's against TSR rules, and there will be someone on my case against it (which is fair to be honest).

I can give you the following though
y/(x^2) = y*x^(-2)

What does the star mean?
Original post by 2939HIHI
What does the star mean?

multiplication. so y times (x to raised to the power -2)

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