Cos10+cos80/sin10+sin80=1

Evaluate cos (10) cos10 to get 0.984807750.98480775. 0.98480775 cos (80) - sin (10) sin (80) 0.98480775⁢ cos80 - ⁢ sin10 ⁢ sin80 Evaluate cos (80) cos80 to get 0.173648170.17364817. 0.98480775⋅0.17364817 - sin (10) sin (80) 0.98480775⋅0.17364817 - ⁢ sin10 ⁢ sin80 Multiply 0.984807750.98480775 by 0.173648170.17364817 to get 0.171010070.17101007. 0.17101007 - sin (10) sin (80) 0.17101007 - ⁢ sin10 ⁢ sin80 Evaluate sin (10) sin10 to get 0.173648170.17364817. 0.17101007 - 1 ⋅0.17364817 sin (80) 0.17101007 - 1 ⋅0.17364817 ⁢ sin80 Multiply - 1 - 1 by 0.173648170.17364817 to get - 0.17364817 - 0.17364817. 0.17101007 - 0.17364817 sin (80) 0.17101007 - 0.17364817 ⁢ sin80 Evaluate sin (80) sin80 to get 0.984807750.98480775. 0.17101007 - 0.17364817 ⋅0.98480775 0.17101007 - 0.17364817 ⋅0.98480775 Multiply - 0.17364817 - 0.17364817 by 0.984807750.98480775 to get - 0.17101007 - 0.17101007. 0.17101007 - 0.17101007 0.17101007 - 0.17101007 Subtract 0.171010070.17101007 from 0.171010070.17101007 to get 0.0