Question

please solve this problem ​

Answer 1

Step-by-step explanation:

i) A+B+C=180

and A+B+C/2=90

therefore, A+B/2=90-(C/2)

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

and sin(90-x)=cos(x)

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

ii) Use the same steps with tan(90-x)=cot(x)