Help Proving ABC is Acute Triangle with Altitudes

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SUMMARY

The discussion centers on proving that points B1, C1, and A2 are collinear in an acute triangle ABC, where A1, B1, and C1 are the feet of the altitudes from vertices A, B, and C respectively. The user suggests utilizing complex numbers or coordinate geometry as potential methods for the proof, while also mentioning an unsuccessful attempt with angle chasing geometry. The focus is on finding a method rather than a complete proof.

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  • Understanding of acute triangles and their properties
  • Familiarity with the concept of altitudes in triangles
  • Knowledge of coordinate geometry techniques
  • Basic principles of complex numbers in geometry
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Vishalrox
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I need help in this ques !

ABC is acute triangle. A1, B1, C1 are foot of altitudes. A1 is reflected about AC to get A2. Prove that B1, C1, A2 are collinear...i couldn't evn figure out how to solve it...but i need it just tell me the method no need to proove...or just tell me the idea how to proove...i need it...plez don't remove this ques...

I tried with the method of Angle chase geometry..but still couldn't get...
 
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Try using complex numbers or coordinate geometry.
 

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