If O is the origin and Q is a variable point on y2 = x, Find the locus of the mid-point of OQ.

Key points to solve the problem:


Idea of section formula- Let two points A(x1,y1) and B(x2,y2) forms a line segment. If a point C(x,y) divides line segment AB in the ratio of m:n internally, then coordinates of C is given as:


C = when m = n =1 , C becomes the midpoint of AB and C is given as C =


How to approach: To find the locus of a point we first assume the coordinate of the point to be (h, k) and write a mathematical equation as per the conditions mentioned in the question and finally replace (h, k) with (x, y) to get the locus of the point.


Let the coordinates of a point whose locus is to be determined to be (h, k). Name the moving point to be C


As, coordinate of mid point is (h,k) {by our assumption},


Let Q(a,b) be the point such that Q lies on curve y2 = x


b2 = a ……equation 1


According to question C is the midpoint of OQ


C = C =



Similarly,


Putting values of a and b in equation 1,we have:



Replace (h,k) with (x,y)


Thus, the locus of a point is: ….ans


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