n+1 chia hết cho 15

=> n+1 \(\in B\left(15\right)\)

=> n+1 \(\in\left\{0;15;30;45;...\right\}\)

=> n \(\in\left\{-1;14;29;44;...\right\}\)

1001 chia hết cho n+1

=> n+1 \(\inƯ\left(1001\right)\)

=> n+1 \(\in\left\{1;7;143;1001\right\}\)

=> n \(\in\left\{0;6;142;1000\right\}\)

\(VP=\sqrt{\frac{a+\sqrt{a^2-b}}{2}}+\sqrt{\frac{a-\sqrt{a^2-b}}{2}}\)

\(VP^2=\frac{a+\sqrt{a^2-b}}{2}+\frac{a-\sqrt{a^2-b}}{2}+2\sqrt{\frac{\left(a+\sqrt{a^2-b}\right)\left(a-\sqrt{a^2-b}\right)}{2.2}}\)

\(=a+\sqrt{\left[a^2-\left(a^2-b\right)\right]}=a+\sqrt{b}\)

\(\Rightarrow VP=\sqrt{a+\sqrt{b}}=VT\)