Answer:
4
Step-by-step explanation:
Given :
f(x) = x² - 6x + 8
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Solving :
Splitting the middle term :
⇒ f(x) = x² - 6x + 8
⇒ f(x) = x² - 2x - 4x + 8
⇒ f(x) = x (x - 2) - 4 (x - 2)
⇒ f(x) = (x - 4)(x - 2)
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Solutions :
⇒ x - 4 = 0 ⇒ x = 4
⇒ x - 2 = 0 ⇒ x = 2
