Question

cosec² 72°- tan² 18° =1
$cosec² 72°- tan² 18° =1$


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Answer 1

Answer:

Step-by-step explanation:

As you know 1+cot^2(72)°=cosec^2(72)°

According to question:-

Cosec² 72°- tan² 18° =

1+Cot² 72°-tan² 18° =

1+Cot²(90°-18°)-tan² 18° =

1+tan² 18°-tan² 18°=1

Hence proved