If 3 cot A = 4, check whether or not

It is given that 3cot A = 4

Or,

Consider a right triangle ABC, right-angled at point B

If AB is 4k, then BC will be 3k, where k is a positive integer

In ΔABC,

(AC)² = (AB)² + (BC)²

= (4k)² + (3k)²

= 16k² + 9k²

= 25k²

AC = 5k

Therefore,

1 – tan²A/1 + tan²A = Cos²A – Sin²A