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 Question from Richard, a student: Dear Sir/ madam, This is my question about sequences. Write down the nth term of the following sequences. 1/2, -3/4, 9/8, -27/16 Plz help me solve the question! Thanks a lot! Richard

Hi Richard,

In this sequence the numerators are powers of 3 (with alternating signs) and the denominators are powers of 2. Ignoring the alternating sign the numerators and denominators are

term number 1 2 3 4 ··· n
numerator 30 31 32 33 ···
denominator 21 22 23 24 ···

What values belong in the n column? To include the alternating sign multiply by (-1)n or (-1)n+1, whichever one works.

I hope this helps,
Penny

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