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Sequences and Series question

2023 · 31 Jan · Shift 1 · Q44

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JEE Main
Mathematics
Sequences and Series
2023 · 31 Jan · Shift 1 · Q44

Sequences and Series question

2023 · 31 Jan · Shift 1 · Q44

JEE MainMathematicsSequences and SeriesNumerical+4 / −1

Let

a_{1}, a_{2}, \ldots, a_{n}

be in A.P. If

a_{5}=2 a_{7}

and

a_{11}=18

, then

12\left(\frac{1}{\sqrt{a_{10}}+\sqrt{a_{11}}}+\frac{1}{\sqrt{a_{11}}+\sqrt{a_{12}}}+\ldots+\frac{1}{\sqrt{a_{17}}+\sqrt{a_{18}}}\right)

is equal to

\underline{\hspace{2cm}}

.

Numerical answer

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