Question

B) prove that tan 6° x tan 21° x tan 30° x tan 69° x tan84 =1/√3

Answer 1

Answer:

tan 6° x tan21° x tan30° x tan69° x tan84°

= cot (90-6)° x cot (90-21)° x tan30° × tan69° x tan84°

= cot 84° x cot 69° x tan30° x tan69° x tan84°

cot84° x tan84°=1 and cot 69° x tan 69°=1

= tan 30°

= 1/√3

= RHS