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ABC is a right angle triangle at C, let BC=a , CA=b and AB=c, and let p be the length of perpendicular from C on AB. prove thay 1/p^2= 1/a^2 + 1/b^2. |
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Answer» Answer: Let CD⊥AB. Then, CD=p ∴ Area of ΔABC= 2 1
(Base×Height) = 2 1
(AB×CD)= 2 1
cp Also, Area of ΔABC= 2 1
2 1
ab ∴ 2 1
cp= 2 1
ab ⇒cp=ab (ii) Since ΔABC is a RIGHT triangle, right angled at C. ∴AB 2 =BC 2 +AC 2
⇒c 2 =a 2 +b 2
⇒( p ab
) 2 =a 2 +b 2 [∵cp=ab⇒c= p ab
] ⇒ p 2
a 2 b 2
=a 2 +b 2
⇒ p 2
1
= b 2
1
+ a 2
1
⇒ p 2
1
= a 2
1
+ b 2
1
Step-by-step EXPLANATION: please mark me BRAINLIST |
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