A parabola and its directrix in red. Two tangents intersect at a point on the directrix. What’s the angle α?
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The grazing shot
Tag: angle
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Worlds colliding
Two intersecting circles and a circle passing through both their centres and their intersection points. What’s the angle α?
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The parallax effect
Two intersecting circles with a triangle that passes through their centres and an intersection point. What’s the angle α?
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Under the volcano
A square containing a right isosceles and an equilateral triangle. What’s the angle α?
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The queen
A cyclic quadrilateral with extended sides and two tangents forming an angle γ. What is γ in terms of α and β?
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The fish trap
Two intersecting circles and two common tangents. Prove that α = β.
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Eternal snow
A triangle with two angle bisectors. What fraction of its area is green?
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The guylines
Two squares and an extended side. What’s the angle α?
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The inner circle
A triangle with its incircle. A line segment through two tangency points and one through the incentre. What’s the angle α?
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Know all angles
A triangle with its circumcircle and circumcentre. What’s α : β?