Question

If the bisector of the angle A is at right angles to the side BC, then evaluate ∠B-∠C. * 2 points ''anser fast''

Answer 1

Answer:

Correct option is

A

AE is H.M. of b and c

B

AD=b+c2bccos2A

C

EF=b+c4bcsin2A

D

the triangle AEF is isosceles.

Given, internal angle bisector of A meets BC at D,

we know length of AD is given by, AD = b+c2bccos2A

Given, △ADE is right angled triangle with right angle at D.

 

∠D=90∘,∠AED=90−2A

Using sine rule in △ADE, we get

sin∠AEDAD=sin∠ADEAE=sin∠2ADE

cos2AAD=AE=sin2ADE

Substitute the value of AD in above equation, we get

AE=cos2Ab+c

Step-by-step explanation:

I hope this is helpful for you