[cos40°+sin50°(1+√3tan10°)]/[sin70°√(1+cos40°)]=[cos40°+sin50°×（tan60°-tan10°）/tan50°]/sin70°(√2)cos20°=[cos40°+（tan60°-tan10°）cos50°]/sin70°(√2)cos20°=[cos40°+√3cos50°-t...