[tex]A=2015x+2016\sqrt{1-x^2}[/tex]
Điều kiện:[tex]-1\leq x\leq 1[/tex]
Ta có:
[tex]A^{2}=\left ( 2015x+2016\sqrt{1-x^{2}} \right )^{2}[/tex]
[tex]\leq \left ( 2015^{2}+2016^{2} \right )\left ( x^{2}+1-x^{2} \right )[/tex]
[tex]=8124481[/tex]
[tex]\Rightarrow A\leq \sqrt{8124481}[/tex]