To factor the expression x3 + x2 + x + 1 by grouping, we can start by rearranging it in pairs for easier factorization.
First, we can group the first two terms and the last two terms:
(x3 + x2) + (x + 1)
Now, we can factor out the common factors from each group:
- From the first group (x3 + x2), we can factor out x2, leading to:
x2(x + 1)
- From the second group (x + 1), we can factor out 1 (as it does not change anything), leading to:
1(x + 1)
Putting it all together, we have:
x2(x + 1) + 1(x + 1)
Notice that (x + 1) is a common factor now, so we can factor that out:
(x + 1)(x2 + 1)
Thus, the final factored form of the expression x3 + x2 + x + 1 by grouping is:
(x + 1)(x2 + 1)