Find the equation of the

Prove ΔAOB=constantProof:xy=c^2 => xy'+y=0 y'=-y/x=-(c/t)/ct=-1/t^2=(y-c/t)/(x-ct)=> x+yt^2=2ctx=0, y=2c/t => B=(0,2c/t)y=0, x=2ct => A=(2ct,0)
ΔAOB=Ax*By/2=2ct*2c/2t=2c^2=constant.......ans

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