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ABC is an acute angled triangle with cir...

ABC is an acute angled triangle with circumcenter O and orthocentre H. If AO=AH, then find the angle A.

Text Solution

Verified by Experts

Given that `OA = HA`
`rArr R = 2R cos A`
`rArr cos A = (1)/(2) " or " A = (pi)/(3)`
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CENGAGE PUBLICATION-PROPERTIES AND SOLUTIONS OF TRIANGLE-Illustration
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