Find three numbers a, b,c between 2 & 18 such that; O their sum is 25 @ the numbers 2, a, b are consecutive terms of an AP & Q.3 the numbers b?c?18 are consecutive terms ofa GP

Options

A. `((a+c)(3a -c))/(4a^2 c^2)`
B. `2/(bc)-1/b^2`
C. `2/(bc)-1/b^2`
D. `((a-c)(3a+c))/(4a^2c^2)`

Answer

A, B

Explanation

`(1/b+1/c-1/a)(1/c+1/a-1b)`
`=(1/b+1/c-2/b+1/c)(1/c+1/b-1/c)`
Also by eliminating b, we get the given expression
`((a+c)(3a-c))/(4a^(2)c^(2))`