SOLUTION: Let (a) and (b) be two solutions of the equation X^2–x+4=0 Then b/a + a/b= ?

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Question 878745: Let (a) and (b) be two solutions of the equation X^2–x+4=0
Then b/a + a/b= ?
Answer by k007sam(3) About Me  (Show Source):
You can put this solution on YOUR website!
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%28-%28-1%29+%2B-+sqrt%28+%28-1%29%5E2-4%2A%281%29%2A%284%29%29%29%2F%282%2A1%29
applying the direct formula.
we get,
x+=+1+%2B-+sqrt%2815%29
that is a+=+1%2Bsqrt%2815%29
and b+=+1-sqrt%2815%29
then u get::::: b/a + a/b =

u need to solve this like this :
+%28b%5E2+%2B+a%5E2%29%2Fab+
so,
%28%281+-+sqrt%2815%29%29%5E2%29+%2B+%281+%2B+sqrt%2815%29%29%5E2%29%29X1%2F%281%5E2+-+sqrt%2815%29%5E2%29
solving further,
+%281+-+15+-+2%2Asqrt%2815%29+%2B+1+%2B+15+%2B+2%2Asqrt%2815%29%29%2F%28-14%29+

cancel out + -+15+-+2%2Asqrt%2815%29 and %2B+15+%2B+2%2Asqrt%2815%29
we get +-2%2F14+ which is +-+1%2F7+