Question

In ΔABC, express $\sum r_1\ cot\frac{A}{2}$ in terms of s.

Answer 1

Solution :

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We know that ,

i ) r1 = s × tanA/2,

ii ) r2 = s × tanB/2

iii ) r3 = s× tanC/2

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Given ,

r1 cotA/2 + r2 cotB/2 + r3 cotC/2

= s × tanA/2cotA/2

+ s × tanB/2cotB/2

+ s × tanC/2cotC/2

= s + s + s

= 3s

•••••

Given r1cotA/2+r2 cotB/2+r3 cotC/2

=

Answer 2

HELLO DEAR,

Answer:

Step-by-step explanation:

We know that ,

r1 = s × tanA/2,

r2 = s × tanB/2

r3 = s× tanC/2

Given ,

r1 cotA/2 + r2 cotB/2 + r3 cotC/2

= s × tanA/2cotA/2 + s × tanB/2cotB/2

+ s × tanC/2cotC/2

=> s + s + s

=> 3s

I HOPE IT'S HELP YOU DEAR,

THANKS