One side of a square makes an angle `alpha` with x axis and one vertex of the square is at origin. Prote that the equations of its diagonals are `x(sin alpha+ cos alpha) =y (cosalpha-sinalpha)` or `x(cos alpha-sin alpha) + y (sin alpha + cos alpha) = a`, where a is the length of the side of the square.

Explanation

Let,`/_XOA=alpha` and `OA=a`


So coordinates of A `(acosalpha,asinalpha)`


And,

`/_XOB=45+alpha `and `OB=OB=sqrt(2)`
a

Similarly, coordiantes of B (`sqrt(2)
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