Question

Can you prove ? (a+b)(b+c)(c+d)>8 a>0 ; b>0 ; c>0

Answer 1

See a solution process below:

Explanation:

To disprove something you only need to find 1 example where the proposed statement is false.

If we let `a` and `b` and `c` all equal `1/2` we would have:

`(1/2 + 1/2)(1/2 + 1/2)(1/2 + 1/2) > 8`

`1 * 1 * 1 > 8`

`1 > 8` which is not a true statement.

There for we cannot prove this statement.