Question

if sin theta= ab then cos theta is?

Answer 1

given sinθ=ab
we know sin²θ + cos²θ = 1 
so, we can now proceed as follows :
=> sin²θ + cos²θ = 1 
=> (ab)² + cos²θ = 1 
=> cos²θ = 1 - a²b²
=> cosθ =√(1 - a²b²) [answer]