tan1°×tan2°xtan3°×...×tan89° এর মান নির্ণয় করো।
Loading content...
tan1° \(\times\) tan2° \(\times\) tan3°....\(\times\) tan89°
=[tan1° \(\times\) tan89°]\(\times\)[tan2° \(\times\)tan88°]\(\times\)[tan3° \(\times\) tan87°]\(\cdot \cdot \cdot\)\(\times\)[tan44° \(\times\) tan46°] \(\times\) tan45°
=[tan1° \(\times\) tan(90°-1°)]\(\times\)[tan2° \(\times\)tan(90°-2°)]\(\times\)[tan3° \(\times\) tan(90°-3°)]\(\times\) \(\cdot \cdot \cdot\)\(\times\)[tan44° \(\times\) tan(90°-44°)] \(\times\) tan45°
=[tan1° \(\times\) cot1°]\(\times\)[tan2° \(\times\)cot2°]\(\times\)[tan3° \(\times\) cot3°] \(\times\) \(\cdot \cdot \cdot\)\(\times\)[tan44° \(\times\) cot44°] \(\times\) tan45°
=1\(\times\) 1\(\times\) 1\(\times\) \(\cdot \cdot \cdot\)\(\times\)1\(\times\) 1
=1