If `x, y in [0,2pi]` then find the total number of order pair `(x,y)` satisfying the equation `sinx .cos y = 1`

Explanation

`sinxcosy = 1`

`=> cosy = 1/sinx`

`=> cosy = cosec x`

Now, there are only two cases when `cos theta and cosec theta ` are equal.
When both of them are `1` or `-1`.

Case 1: When `cos y = cosecx = 1`

`=>cos y = 1 , cosecx =1`

`=>y = 0,2pi and x = pi/2`

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