The mistake is factorization of 12x² 17x - 5 in step 2 instead of 12x² + 7x - 1 and the factored form is 2x(12x - 5)(x + 1).
What is factorization of polynomial?
Given
24x³ + 34x² - 10x
Factor 2x from the expression
2x(12x² 17x - 5)
Factorize the expression inside the parentheses.
2x( 12x² + 12x + 5x - 5)
2x(12x(x + 1) - 5(x + 1)
2x(12x - 5)(x + 1)
The mistake is that instead of factorizing the expression the 12x² 17x - 5 in step 2 he factorized 12x² + 7x - 1.
The factored expression is
2x( 12x² + 12x + 5x - 5)
2x(12x(x + 1) - 5(x + 1)
2x(12x - 5)(x + 1).
Therefore, the mistake is factorization of 12x² 17x - 5 in step 2 instead of 12x² + 7x - 1 and the factored form is 2x(12x - 5)(x + 1).