Math, asked by pankajjaat6, 1 year ago

prove that The sum of Three altitude of triangle is less than the sum of three side of angles

Answers

Answered by theliteldino
5

Let the altitudes through A, B, C be AD, BE, CF

AB > AD (Hypotenuse is longer than any side of the right triangle [ABD])

Similarly, AC > AD

Adding both, AB + AC > 2AD

Similarly, AB + BC > 2 BE & BC + AC > 2CF

Adding all three eqns.

2(AB + BC + AC) > 2(AD + BE + CF)

AB + BC + AC > AD + BE + CF




theliteldino: You can use the figure in your book
Answered by Anonymous
13

Answer:

ABC is a triangle ,AD ,BE and CF are Altitudes on side

BC ,AC and AB

Now in ABD , D is 90° ,B is acute angle

So D > B

 AB > AD -------(1) [side opposite to the greater angle is also greater]

And, In ADC , D is 90° ,C is acute angle

So D > C

 AC > AD -------(2) [side opposite to the greater angle is also greater]

And, In BFC , F is 90° ,B is acute angleSo F > B

 BC > CF -------(3) [side opposite to the greater angle is also greater]

And, In AFC , F is 90° ,A is acute angle

So F > A

 AC > CF -------(4) [side opposite to the greater angle is also greater]

And, In ABE , E is 90° ,A is acute angle

So E > A

 AB > BE -------(5) [side opposite to the greater angle is also greater]

And, In BEC , E is 90° ,C is acute angle

So E > C

 BC > BE -------(6) [side opposite to the greater angle is also greater]

On Adding eq (1)(2)(3)(4)(5)and (6)

AB+AC+BC+AC+AB+BC > AD+AD+CF+CF+BE+BE

2AB+2BC+2AC > 2AD +2CF+2BE

2(AB+BC+AC) > 2(AD+CF+BE)

AB+BC+AC > AD +BE +CF

Hence Proved.

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