Question

If sec A + tan A = x, then sec A =

a) x2 - 1 / x
b) x2 +1 / x
c) x2 - 1 / 2x
d) x2 + 1 / 2x​

Answer 1

Answer:

If sec A + tan A = x, then sec A =

a) x2 - 1 / x

Answer 2

Answer:

We know that

sec²A - tan²A = 1 ___(1)

a²-b²= (a+b)(a-b) ___(2)

By using these two formulae, we get

secA - tanA = 1/x

Add these two equations, then you get

secA = 1/2(x + 1/x) or x/2 + 1/2x