Question

If a sec∅ - b tan ∅ = 1 and
a²sec² ∅ - b² tan²∅ = 5, then
(4a²-9b²) = ?​

Answer 1

Answer:

a sec theta+b tan theta=5

sec theta=3/a(1)

tan theta=2/b(2)

square of (1) and (2) after it, it's difference

9/a^2-4/b^2=

9b^2-4a^2=(ab)^2

4a^2-9b^2=-(ab)^2