Answer:
[tex]\frac{1}{2}[/tex] (a + 2b)(a - b)
Step-by-step explanation:
Assuming you require the expression to be factored
Given
[tex]\frac{1}{2}[/tex] a² + [tex]\frac{1}{2}[/tex] ab - b² ← factor out [tex]\frac{1}{2}[/tex] from each term
= [tex]\frac{1}{2}[/tex] (a² + ab - 2b²) ← factor the quadratic
Consider the factors of the coefficient of the b² term(- 2) which sum to give the coefficient of the ab- term (+ 1)
The factors are + 2 and - 1, since
2 × - 1 = - 2 and 2 - 1 = + 1, thus
a² + ab - 2b² = (a + 2b)(a - b) and
[tex]\frac{1}{2}[/tex] a² + [tex]\frac{1}{2}[/tex] ab - b² = [tex]\frac{1}{2}[/tex](a + 2b)(a - b)