What value of x will make the function x(4 – x) a maximum?

A.
4 
B.
3 
C.
2 
D.
1
Correct Answer: Option C
Explanation
x(4 – x)
4x – x^{2}
(frac{dy}{dx}) = 4 – 2x
(frac{dy}{dx}) = 0
2x = 4
x = (frac{4}{2})
= 2
x(4 – x)
4x – x^{2}
(frac{dy}{dx}) = 4 – 2x
(frac{dy}{dx}) = 0
2x = 4
x = (frac{4}{2})
= 2