Question

sec A + tan A = 3, then find sec A​

Answer 1

Answer:

Step-by-step explanation:

Sec² A - Tan² A = 1

=> x² - y² = (x+y) (x-y)

__________________

Given

---------

Sec A + Tan A = 3....... (1)

__________________

So,

Sec² A - Tan² A = 1

Now adding equation (1) and (2) we get,

Sec A + Tan A = 3

+ Sec A - Tan A = ⅓

------------------------------

2 Sec A = 3 +⅓

or, Sec A = ½ × (9+1)/3 = ½× 10/3

or, Sec A = 5/3

Answer 2

Answer : 5/3

Solution :

Given that :

secA + tanA = 3

=> tanA = 3 - secA

On squaring both the sides :

tan²A = 9 - 6secA + sec²A

{ (a-b)² = a²-2ab+b² }

6secA - 9 = sec²A - tan²A

As we know that :

sec²A = 1 + tan²A => sec²A - tan²A = 1

Then, 6secA - 9 = 1

=> 6secA = 10

=> secA = 10/6

=> secA = 5/3

@ItsChampion ✌️