JEE Main 2006Annual, Paper 1MathematicsMediumSequence and Series179× since 2002If a1,a2,....an{{a_1},{a_2},....{a_n}}a1,a2,....an are in H.P., then the expression a1 a2+ a2 a3 +....+an−1 an{{a_1}\,{a_2} + \,{a_2}\,{a_3}\, + .... + {a_{n - 1}}\,{a_n}}a1a2+a2a3+....+an−1an is equal toAOption A. n(a1 −an)n({a_1}\, - {a_n})n(a1−an)BOption B. (n−1)(a1 −an)(n - 1)({a_1}\, - {a_n})(n−1)(a1−an)COption C. na1ann{a_1}{a_n}na1anDOption D. (n−1) a1an(n - 1)\,\,{a_1}{a_n}(n−1)a1anCheckSkip · show solution
