It should be 6, radius is half of the circumference (6/3=2).
Answer:C=2πr=2·π·2≈12.56637in
Step-by-step explanation:

Divide both side by
and rearrange terms to get a linear ODE;

Multiply both sides by
:

The left side can be condensed as the derivative of a product:

Integrate both sides, then solve for
:

Answer:
a ≠ 2
Step-by-step explanation:
Given

The denominator of the rational function cannot be zero as this would make it undefined. Equating the denominator to zero and solving gives the value that a cannot be, that is
- 3a + 6 = 0 ( subtract 6 from both sides )
- 3a = - 6 ( divide both sides by - 3 )
a = 2 ← excluded value