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# If r and t are positive integers, what is the value of t?

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Re: If r and t are positive integers, what is the value of t? [#permalink]
aj0809
Hi All,

Thanks

Yes, we can.

t^(r-1) = t^r * t^(-1)

and t ^ (-1) = 1/t

so...

t^(r-1) = t^r / t

I hope it's clear.

Thanks
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Re: If r and t are positive integers, what is the value of t? [#permalink]
Hi All,

DesiGmat is correct, but for the sake of removing any confusion on the subject, I'm just going to add some parentheses:

T^(R-1) = (T^R)/T

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Rich
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Re: If r and t are positive integers, what is the value of t? [#permalink]
aj0809
Hi All,

Thanks

See in solving the questions pertaining to exponents we need to remember the EXPONENT 1 rules
1=> (1)^anything =1
2=> (-1)^any even positive number =1
3=> (any number) ^0 =1 (any number ≠0)

Hope this helps

regards
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If r and t are positive integers, what is the value of t? [#permalink]
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MHIKER
If r and t are positive integers, what is the value of t?

(1) $$t^{r-1} = 1$$

(2) $$r ≠ 1$$

(1) If r=1, them $$t^{1-1}=t^0=1$$, t can take any value. Insufficient.

(2) We don't have any information about t. Insufficient.

Considering both:

$$t^{r-1} = 1$$, and $$r ≠ 1$$, then t must 1 as any exponent of 1 will result 1. Sufficient.

The answer is $$C.$$
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Re: If r and t are positive integers, what is the value of t? [#permalink]
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Re: If r and t are positive integers, what is the value of t? [#permalink]
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