Question

if tan(A+B)=1 and cos A=1.find sinB

Answer 1

i) tan(A+B)=1
tan(A+B)=tan 45
A+B=45---(1)
ii)cos A=1
cos A= cos 0
A=0----(2)
put A=0 in (1)
B=45
sin B= sin 45
=1/(root 2)