Two circles intersect at A and B. P is a point on produced BA. PT and ...
We know that,
Property- If MNO is a secant to a circle intersecting the circle at M and N and OT is a tangent segment, then
OM × ON = OT
2From the diagram,
PAB is a secant to a circle with center O
1 intersecting the circle at A and B and PT is a tangent segment,
∴ PA × PB = PT
2 ……. (1)
Again, PAB is a secant to a circle with center O
2 intersecting the circle at A and B and PQ is a tangent segment,
∴ PA × PB = PQ
2 ……. (2)
From (1) and (2)
PT
2 = PQ
2⇒ PT = PQ
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Two circles intersect at A and B. P is a point on produced BA. PT and ...
We can use the power of a point theorem to find the relation between PT and PQ.
Let O1 and O2 be the centers of the circles. Then, we have:
AP^2 = AB * AP = (AO1 + BO1) * (AO2 - BO2)
AQ^2 = AB * AQ = (AO1 - BO1) * (AO2 + BO2)
Note that AO1 = AO2 (since they are radii of the same circle) and BO1 = BO2 (since they are radii of the other circle).
Adding the two equations, we get:
AP^2 + AQ^2 = 2AO1 * AO2
Now, let's consider the right triangles APT and APQ. Since PT and PQ are tangents to the circles, we have:
AT = AQ and AP = AP (common side and radii of the same circle)
AP > PT and AP > PQ (since PT and PQ are tangents)
Therefore, we have:
PT^2 = AP^2 - AT^2
PQ^2 = AP^2 - AQ^2
Substituting AT = AQ into the second equation and adding the two equations, we get:
PT^2 + PQ^2 = 2AP^2 - 2AO1 * AO2
Using the first equation above, we can simplify this to:
PT^2 + PQ^2 = 2AP^2 - (AP^2 + AQ^2)
PT^2 + PQ^2 = AP^2 - AQ^2
Substituting AQ^2 = AP^2 - 2AO1 * AO2 from the first equation, we get:
PT^2 + PQ^2 = 2AP^2 - 2AO1 * AO2
Comparing this with the earlier equation for AP^2 + AQ^2, we see that:
PT^2 + PQ^2 = 2(AP^2 + AQ^2) - 4AO1 * AO2
PT^2 + PQ^2 = 2(2AO1 * AO2) - 4AO1 * AO2
PT^2 + PQ^2 = 0
Therefore, we have:
PT^2 = -PQ^2
PT = i * PQ
where i is the imaginary unit.
Thus, the relation between PT and PQ is:
PT = i * PQ