Question 12
For real $x$, find the maximum of $A=\dfrac{10}{\sqrt{x^2+14x+99}}$.
HKIMO 2026 THPT (Grades 10–12 shared) National Preliminary Set 04 Question 12
HKIMO · HKIMO 2026 THPT (Grades 10–12 shared) National Preliminary Set 04
HKIMO · HKIMO 2026 THPT (Grades 10–12 shared) National Preliminary Set 04