Question

25) If sec A + tan A = m and sec A-tan A = n, then show that mn = 1.​

Answer 1

Step-by-step explanation:

Given secA +tanA=m and secA-tanA=n

To prove:- mn=1

L.H.S. mn=(secA+tanA)(secA-tanA)

= sec2A - tan2A [by using identity (a+b)(a-b)=a2 - b2 ]

= 1+tan2A - tan2A [by using identity sec2A=1+tan2A ]

= 1=R.H.S. H.Proved

Answer 2

Answer:

(sec A + tan A)(sec A-tan A)

Step-by-step explanation:

sec sq 2A - tansq2 A

1/cos^2A - sin^2/cos^2

1