1let a,b& c b roots of given equation
using product of roots
abc = -r ..........bt ab=-1 (frm ques)
==> c = r .................(1)
applying sum of roots
a+b+c = -p
==> a+ b+r = -p (by eq 1)
==> a+b+p+r =0
==>r(a+b+p+r)=0
hence proved
Few quaries , trying to do them myself ---- would be glad to get help ----
1 > The cubic equation , x3 + px2 + qx + r = 0 has two roots “ a “ and “ b “ such that ab + 1 = 0 .
Prove that r ( r + a+ b + p ) = 0 .
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