令x=0f(x)=0+1-1=0所以 若f(x)为常值函数,则f(x)=0令x=π/2f(x)=sinkπ/2-(-1)^k=0 (k为自然数)设m为自然数当k=4mf(x)=sin2mπ-1=0m无解当k=4m-3f(x)=sin(2mπ-3π/2)+1=0m无解当k=4m-2f(x)=sin(2mπ-π)-1=0m无解当...