2. Confirm that 1+V5 and 1 - V5 are the correct roots for x2 – 2x – 4 = 0.
1 answer:
Answer:
see explanation
Step-by-step explanation:
Given
x² - 2x - 4 = 0 ( add 4 to both sides )
x² - 2x = 4
To solve use the method of completing the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(- 1)x + 1 = 4 + 1
(x - 1)² = 5 ( take the square root of both sides )
x - 1 = ± ( add 1 to both sides )
x = 1 ± , thus
x = 1 + or x = 1 -
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