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The value of b for which the equations x2+bx−1=0 and x2+x+b=0
have no root in common is
Explanation
For common root x:
Substitute x in (2):
(b+1)2+(b+1)(b−1)+b(b−1)2=0
b2+2b+1+b2−1+b(b2−2b+1)=0
Common root values:
Since −i5 is not in {0,i3,−i3}, it satisfies the condition for no common root.
Correct Option:
Explanation
For common root x:
Substitute x in (2):
(b+1)2+(b+1)(b−1)+b(b−1)2=0
b2+2b+1+b2−1+b(b2−2b+1)=0
Common root values:
Since −i5 is not in {0,i3,−i3}, it satisfies the condition for no common root.
Correct Option: