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In triangle ABC, AB = AC and BD is perpendicular to AC. Prove that: BD2 - CD2 = 2CD × AD - Mathematics

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प्रश्न

In triangle ABC, AB = AC and BD is perpendicular to AC.

Prove that: BD2 - CD2 = 2CD × AD

बेरीज

उत्तर


In right-angled ΔADB,

BD2 = AB2 + AD             ...(Pythagoras theorem)

⇒ BD2 = AC2 - AD2           

⇒ BD2 = (AD + DC)2 - AD2

⇒ BD2 = AD2 + CD2 + 2AD × DC - AD2

⇒ BD2 - DC2 = 2AD × DC

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  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 13: Pythagoras Theorem [Proof and Simple Applications with Converse] - Exercise 13 (B) [पृष्ठ १६४]

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सेलिना Concise Mathematics [English] Class 9 ICSE
पाठ 13 Pythagoras Theorem [Proof and Simple Applications with Converse]
Exercise 13 (B) | Q 14 | पृष्ठ १६४

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