Hãy tính \(\left( {\tan {{52}^ \circ } + \cot {{43}^ \circ }} \right).\left( {\tan {{29}^ \circ } - \cot {{61}^ \circ }} \right).\left( {\tan {{13}^ \circ } - \tan {{24}^ \circ }}...

* Hướng dẫn giải

Ta có:

\( \tan {29^ \circ } = \cot {61^ \circ }\: \Rightarrow \tan {29^ \circ } - \cot {61^ \circ } = 0\)

Do đó: 

\( \left( {\tan {{52}^ \circ } + \cot {{43}^ \circ }} \right).\left( {\tan {{29}^ \circ } - \cot {{61}^ \circ }} \right).\left( {\tan {{13}^ \circ } - \tan {{24}^ \circ }} \right) = 0\)