Q18 of 101 Page 24

Show that the point (x, y) given by and lies on a circle for all real values of t such that - 1 ≤ t ≤ 1, where a is any given real number.

Given:


⇒


⇒


We need to prove that the point (x, y) lies on a circle for real values of t such that - 1≤t≤1, where a is any given real number.


Consider x2 + y2,


⇒


⇒


⇒


⇒


⇒


⇒


⇒ x2 + y2 = a2


The point (x,y) lies on a circle.


∴Thus proved.


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