Question

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 α where 0<α<90with the positive direction of x - axis. The equation of its diagonal not passing through the origin is

• A.
• B.
• C.
• D.

Answer 1

The correct option is A

$\therefore$ Required digonal passes through (-a sin $\alpha$ , a cos $\alpha$) and (-a cos $\alpha$ , a sin $\alpha$)

$\therefore$ Required digonal equation is y(cos $\alpha$ , sin $\alpha$) + x( cos $\alpha$ - sin $\alpha$) = a