To factorize the expression (3a-1) - 6 + 2, we can follow these steps:

Step 1: Simplify the expression inside the parentheses. (3a-1) - 6 + 2 becomes 3a - 1 - 6 + 2.

Step 2: Combine like terms. The terms -1, -6, and 2 can be combined to give -5. So, the expression becomes 3a - 5.

Now, let’s factorize the expression 3a - 5.

Step 3: Look for common factors. In this case, there are no common factors other than 1.

Step 4: Check if it is a binomial expression. A binomial expression has two terms separated by either addition or subtraction. In this case, 3a - 5 is a binomial expression.

Step 5: Factorize the expression. To factorize a binomial expression, we look for common factors in both terms. In this case, there are no common factors between 3a and -5.

So, the expression 3a - 5 cannot be further factorized.

Therefore, the factorized form of (3a-1) - 6 + 2 is 3a - 5.

The answer in the book, 3(3a-1) (a-1), is incorrect.