If m is the A.M. of two distinct real numbers `l` and `n""(""l ,""n"">""1)` and` G_1, G_2` and `G_3` are three geometric means between `l` and n, then `G_1^4+2G_2^4+G_3^4` equals, (1) `4l^2` mn (2) `4m^2` nl (3) `4l m n^2` (4) `4l^2m^2n^2`

Explanation

`m= (l+n)/2`

`=> 2m = l+ n`

`G_1 , G_2 , G_3`

`l, G_1, G_2 , G_3 , n`are in GP

let d be the common ration

`G_1 = ld`

`G_2 = ld^2`

`G_3 = ld^3`

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