Question

Let a₁ , a₂ , ……,a_n be in A.P. If a₅ = 2a₇ and a₁₁ = 18, then

\(12(\frac{1}{\sqrt{a_{10}}+\sqrt{a_{11}}}+\frac{1}{\sqrt{a_{11}}+\sqrt{a_{12}}}+...\frac{1}{\sqrt{a_{17}}+\sqrt{a_{18}}})\) is equal to _________.

Answer 1

Correct answer is 8