"A square of side `' a '`  lies above the x-axis and has one vertex at the origin. The side
Channel: Doubtnut
Date: 2020-06-28

"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 (0ltalphaltpi/ 4)` with the positive direction of x-axis. equation its diagonal not passing through origin is: 
 
 a. `y(cosalpha-sinalpha)-x(sinalpha-cosalpha)=a` b. `y(cosalpha+sinalpha)+x(sinalpha-cosalpha)=a` c. `y(cosalpha-sinalpha)+x(sinalpha+cosalpha)=a` d. `y(cosalpha+sinalpha)-x(cosalpha+sinalpha)=a`"