1)if the median of triangle ABC through A is perpendicular to AB, then value of tanA + 2 tanB is......?

2)In a triangle ABC, a=5,b=4 & cos(A-B)=31/32, then side c=.....?

3)if the bisector of angle A of ΔABC makes an angle Φ wid BC, then sinΦ is equal to....?

4)in a triangle ABC, (a+b+c)(b+c-a)=Λbc if......(condition)?

Dear nishat

In Triangle ACD 

 use sine rule

a/2 sinB /sin(180-A-B)   = a/2 /sin(A-90)

sinB/sin(A+B)  = -1/cosA

 sinB cosA = -sin(A+B)

 sinBcosA  =-[sinAcosB + cosA sinB]

 tanA +2tanB =0

post seperate question in different post

     
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