Question

A manufacturer of gas grills has daily production costs of

C = 400 – 5x + 0.125x2, where x is the number of gas grills produced. How many units should be produced each day to yield a minimum cost?

Answer 1

hint : it is a quadratic function , so find minimum
by finding c'(x)
c'(x)=0
x_min is the root(s) of c'=0

Answer 2

\[C = 400 – 5x + 0.125x^2,\] right?

Answer 3

minimum is the second coordinate of the vertex
first coordinate of the vertex is always
\[-\frac{b}{2a}\] which in your case is
\[-\frac{-5}{2\times .125}=20\]

Answer 4

oh they just want the number to make, that answer is 20