Problem Solving (PS) | Re: If r is between –1 and 0, then which of the following is true?

The best way is to choose a number and look at the various options.
If r = -12,r5=−132=−0.03125,r3=−18=−0.12512,r5=−132=−0.03125,r3=−18=−0.125 and r7=−1128=−0.007r7=−1128=−0.007
However, r^even is always positive

Options A,B and C are eliminated because, we have a even power
in between two odd powers and the positive term will always be the biggest.
r7r7 is greater than r5r5, so Option D cannot be the answer.

Therefore, r3<r7<r6r3<r7<r6(Option E) is the answer
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