Question

If sec theta +tan theta =m and sec theta -tan theta =n then show that m×n=1

Answer 1

Answer : (secA+ tanA) (secA-tanA) = mn

[a-b= (a+b) (a-b)]

(sec²A-tan²A). = m n

(sec²A=1+tan²A)

(sec²A-tan²A=1)

Then 1 = mn