Expression 1: sine left parenthesis, "x" , right parenthesis cosine left parenthesis, "y" , right parenthesis positive sine left parenthesis, "y" , right parenthesis cosine left parenthesis, "z" , right parenthesis plus sine left parenthesis, "z" , right parenthesis cosine left parenthesis, "x" , right parenthesis equals 0sinxcosy+sinycosz+sinzcosx=0