[" 40."r_(1)+r_(2)=],[" (a) "c tan((C)/(2))," (b) "c cot((C)/(2))],[" (c) "c sin((C)/(2))," (d) "c cos((C)/(2))]

Show that r_(1)+r_(2)=c cot((C)/(2))

Show that r_(1)+r_(2)=c cot ((C)/(2))

Show that r_(1)+r_(2)=c cot ((C)/(2))

Show that r_(1)+r_(2)=c cot ((C)/(2))

If : A+B+C= pi "then" : 1 - sin^(2)""(A)/(2) - sin^(2)""(B)/(2)+ sin^(2)""(C)/(2)= A) 2cos""(A)/(2) * cos sin ^(2)""(B)/(2) + sin^(2)""(C)/(2) B) 2 cos ""(B)/(2)* cos ""(B)/(2) * sin""(C)/(2) C) 2 cos ""(C)/(2)* cos ""(A)/(2) * sin""(B)/(2) D) 2 cos ""(A)/(2)* cos ""(B)/(2) * sin""(C)/(2)

In triangle ABC, prove that, tan((B-C)/(2))=(b-c)/(b+c)cot((A)/(2)) tan((C-A)/(2))=(c-a)/(c+a)cot((B)/(2)) tan((A-B)/(2))=(a-b)/(a+b)cot((C)/(2))

(cos ^(2) ((B-C)/( 2)) )/( (b+c)^(2))+( sin ^(2)((B-C)/( 2)) )/( (b-c)^(2))=

Prove that : (r_1+r_2) tan (C )/(2) = (r_3- r) cot ( C)/(2) = c

Prove that : (r_1+r_2) tan (C )/(2) = (r_3- r) cot ( C)/(2) = c