We have the following equation:
x2-5x + 1 = 0
Using the resolver we have:
x = (- b +/- root (b2 - 4ac)) / 2a
Substituting values we have:
x = (- (- 5) +/- root ((- 5) 2 - 4 (1) (1))) / 2 (1)
Rewriting:
x = (5 +/- root (25 - 4)) / 2
x = (5 +/- root (21)) / 2
The results are:
x = (5 + root (21)) / 2
x = (5 - root (21)) / 2
Answer:
x = (5 + root (21)) / 2
x = (5 - root (21)) / 2
option D and E