A square of side a lies above the x-axis and has one vertex at the origin. The side passing through the origin makes an angle `alpha(0 lt alpha lt (pi)/(4))` with the positive direction of x-axis. The equation of its diagonal not passing through the origin is :

Options

A. `y(cos alpha+sin alpha)+x(sin alpha-cos alpha)=a`
B. `y(cos alpha+sin alpha)+x(sin alpha+cos alpha)=a`
C. `y(cos alpha+sin alpha)+x(cos alpha-sin alpha)=a`
D. `y(cos alpha-sin alpha)-x(sin alpha-cos alpha)=a`.

Answer

C