Write the first five terms of the sequence defined by the explicit formula a subscript n baseline equals 112 left-parenthesis Start Fraction 1 over 4 End Fraction right-parenthesis superscript n minus 1 baseline.

(1 point)
Responses

112 comma 28 comma 7 comma start fraction 7 over 4 end fraction comma start fraction 7 over 16 end fraction
Image with alt text: 112 comma 28 comma 7 comma start fraction 7 over 4 end fraction comma start fraction 7 over 16 end fraction

112 comma negative 28 comma 7 comma negative start fraction 7 over 4 end fraction comma start fraction 7 over 16 end fraction
Image with alt text: 112 comma negative 28 comma 7 comma negative start fraction 7 over 4 end fraction comma start fraction 7 over 16 end fraction

28 comma 7 comma start fraction 7 over 4 end fraction comma start fraction 7 over 16 end fraction comma start fraction 7 over 64 end fraction
Image with alt text: 28 comma 7 comma start fraction 7 over 4 end fraction comma start fraction 7 over 16 end fraction comma start fraction 7 over 64 end fraction

28 comma negative 7 comma start fraction 7 over 4 end fraction comma negative start fraction 7 over 16 end fraction comma start fraction 7 over 64 end fraction

1 answer

To determine the first five terms of the sequence defined by the formula \( a_n = 112 \left( \frac{1}{4} \right)^{n-1} \), we will evaluate this formula for \( n = 1, 2, 3, 4, \) and \( 5 \).

  1. For \( n = 1 \): \[ a_1 = 112 \left( \frac{1}{4} \right)^{1-1} = 112 \left( \frac{1}{4} \right)^0 = 112 \cdot 1 = 112 \]

  2. For \( n = 2 \): \[ a_2 = 112 \left( \frac{1}{4} \right)^{2-1} = 112 \left( \frac{1}{4} \right)^1 = 112 \cdot \frac{1}{4} = 28 \]

  3. For \( n = 3 \): \[ a_3 = 112 \left( \frac{1}{4} \right)^{3-1} = 112 \left( \frac{1}{4} \right)^2 = 112 \cdot \frac{1}{16} = 7 \]

  4. For \( n = 4 \): \[ a_4 = 112 \left( \frac{1}{4} \right)^{4-1} = 112 \left( \frac{1}{4} \right)^3 = 112 \cdot \frac{1}{64} = \frac{7}{4} \]

  5. For \( n = 5 \): \[ a_5 = 112 \left( \frac{1}{4} \right)^{5-1} = 112 \left( \frac{1}{4} \right)^4 = 112 \cdot \frac{1}{256} = \frac{7}{16} \]

Now, compiling the first five terms, we have:

\[ 112, 28, 7, \frac{7}{4}, \frac{7}{16} \]

Thus, the correct response is:

112, 28, 7, \(\frac{7}{4}\), \(\frac{7}{16}\).