Answer:
The length of AB =

Explanation:
Given
- BC =

So we have to determine the length of AB which is Hypotenuse.
i.e. AB = Hypotenuse = x ?
so
Using the formula
Cos θ = Adjacent / Hypotenuse
Here:
- Adjacent = BC =

so
Cos θ = Adjacent / Hypotenuse
∵ AB = Hypotenuse = x
∵

Therefore, the length of AB =
