Step 1 :
To factor $ x^{3}-2197 $ we can use difference of cubes formula:
$$ I^3 - II^3 = (I - II)(I^2 + I \cdot II + II^2) $$After putting $ I = x $ and $ II = 13 $ , we have:
$$ x^{3}-2197 = ( x-13 ) ( x^{2}+13x+169 ) $$Step 2 :
Step 2: Identify constants $ \color{blue}{ b }$ and $\color{red}{ c }$. ( $ \color{blue}{ b }$ is a number in front of the $ x $ term and $ \color{red}{ c } $ is a constant). In our case:
$$ \color{blue}{ b = 13 } ~ \text{ and } ~ \color{red}{ c = 169 }$$Now we must discover two numbers that sum up to $ \color{blue}{ 13 } $ and multiply to $ \color{red}{ 169 } $.
Step 3: Find out pairs of numbers with a product of $\color{red}{ c = 169 }$.
| PRODUCT = 169 | |
| 1 169 | -1 -169 |
| 13 13 | -13 -13 |
Step 4: Because none of these pairs will give us a sum of $ \color{blue}{ 13 }$, we conclude the polynomial cannot be factored.