Answer: B
Step by Step explanation:
Without any extra conditions, the answer could be 3, and the simplest polynomial with the given roots would be
(<em>x</em> + 5) (<em>x</em> - (1 + 4<em>i</em> )) (<em>x</em> + 4<em>i</em> )
= <em>x</em> ³ + 4<em>x</em> ² + (11 - 4<em>i</em> ) <em>x</em> + 80 - 2<em>i</em>
<em />
If the polynomial is supposed to have only <em>real</em> coefficients, then any complex roots must occur along with their complex conjugates:
(<em>x</em> + 5) (<em>x</em> - (1 + 4<em>i</em> )) (<em>x</em> - (1 - 4<em>i</em> )) (<em>x</em> + 4<em>i</em> ) (<em>x</em> - 4<em>i </em>)
= <em>x</em> ⁵ + 3<em>x</em> ⁴ + 23<em>x</em> ³ + 133<em>x</em> ² + 112<em>x</em> + 1360
and then the degree would be 5.
The answer is B. That is not a valid way to sample as it is not randomly selected.
Answer: C
Step-by-step explanation:
$12.80 × 1.075 = $13.76
$13.76 × 1.15 =$15.82
