In a triangle PQR angle R=90 .If tan P/2 and tan Q/2 are the roots of ax^2 +bx+c=0,a is not equal to 0 then find the relation between a,b and c.

urgent

Answer :
Given
tanP2  And tanQ2  are the roots of ax2 + bx + c = 0
So by relationship between zeros and coefficient , we get

tanP2  + tanQ2 = -ba          -------------- ( 1 )
And
tanP2 tanQ2 = ca                  --------------- ( 2 )
In triangle PQR 
 
So, we know sum of all internal angles in triangle = 180

90 + P + Q = 180 

P + Q = 90

Divide by 2 on both hand side , we get

 P2 + Q2  = 45
Taking tan on both hand side and get

tan ( P2 + Q2 ) = tan 45
 
 tan P2 + tan Q21 - tanP2tanQ2   = 1                 ( As we know tan 45 = 1 )

Substitute values from equation 1 and 2 , and get

-ba1 -ca  = 1 

- b  = a  - c

 c  - a  = b                                   ( Ans )

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