Tough and Tricky questions: Word Problems.
The longevity of a certain metal construction is determined by the following formula: l = (7.5 - x)^4 + 8.97^c, where l is the longevity of the construction, in years, x is the density of the underlying material, in g/cm^3, and c is a positive constant equal to 1.05 for this type of metal constructions. For what value of density, x, expressed in g/cm^3, will the metal construction have minimal longevity?
A. -7.5
B. 0
C. 7.5
D. 15
E. 75
Kudos for a correct solution.