Answer:
Step-by-step explanation:
= x - 5 ( x ≥ 3 )
( )² = ( x - 5 )²
x - 3 = x² - 10x + 25
x² - 11x + 28 = 0
(x - 4)(x - 7) = 0
= 7
= 4
Check the answer:
1). x = 7
= 7 - 2
√4 = 2
2 = 2
2). x = 4
= 4 - 5
1 = - 1 (False statement) ⇒ x = 4 is an extraneous solution.
Answer:
a = - 4
Step-by-step explanation:
Given x = - 2 is a root then f(- 2) = 0
f(x) = x³ + x² + ax - 4, thus
f(- 2) = (- 2)³ + (- 2)² - 2a - 4 = 0, that is
f(- 2) = - 8 + 4 - 2a - 4 = 0, thus
- 8 - 2a = 0 ( add 8 to both sides )
- 2a = 8 ( divide both sides by - 2 )
a = - 4
D, while numbers is the answer
