Question

please can somebody help me with these 2 sums ..​

Answer 1

Answer:

A+B+C=180

B+C=180-A

divide by 2

B+c/2=90-A/2

apply sin^2 O on both sides

sin^2(B+C/2)=sin^2(90-A/2)

sin^2(B+C/2)=cos^2(A/2)

sin^2(B+C/2)=1-sin^2(A/2)

sin^(B+C/2)+sin^2(A/2)=1

next ans I don't have time post me later