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If two circles x2+y2+2gx+2fy=0 and x2+y2+2g′x+2f′y=0 touch each other, then which of the following is true?
- A.
gf=gf′
- B.
g′f=gf′
(Correct Answer) - C.
gg′=ff′
- D.
None of these
Explanation
1. Centers of Circles:
Center C1=(−g,−f)
Center C2=(−g′,−f′)
Point of contact = (0,0) (Origin)
2. Collinearity Condition:
Since both circles touch at the origin, the centers and the origin are collinear.
Slope of OC1=Slope of OC2
3. Final Solving:
Conclusion:
Correct option is (b).
Explanation
1. Centers of Circles:
Center C1=(−g,−f)
Center C2=(−g′,−f′)
Point of contact = (0,0) (Origin)
2. Collinearity Condition:
Since both circles touch at the origin, the centers and the origin are collinear.
Slope of OC1=Slope of OC2
3. Final Solving:
Conclusion:
Correct option is (b).