Question

The expression below is a sum of cubes. 125x3 + 169

Answer 1

125x^3 = (5x)^3
125x^3 is the cube of 5x.

169 = 13^2
169 is the square of 13, but not the cube of a rational number.

The statement is false.

Answer 2

`\text{The expression }125x^3+169\text{ is not the sum of cube}`

Explanation:

Given the expression

`125x^3+169`

we have to tell the above expression is the sum of cube

The sum of cube is of the form

`a^3+b^3` → (1)

`Expression: 125x^3+169`

125 is the cube of 5 and 169 is the square of 13

`125x^3+169`

`(5x)^3+13^2`

Comparing above with equation (1), we see the given expression is not the sum of cube