Mathematics
NULL
Medium
Question
Find the value of a/b + b/a, if a and b are the roots of x² + 8x + 4 = 0.
A
15
B
14
✓ Official correct answer
C
24
D
26
Community credibility
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A
15
No member explanations yet for this option.
B
14
No member explanations yet for this option.
C
24
No member explanations yet for this option.
D
26
No member explanations yet for this option.
Explanation
a + b = −8, ab = 4. a/b + b/a = (a² + b²)/ab = ((a+b)² − 2ab)/ab = (64 − 8)/4 = 14.