Find the locus of the point of intersection of tangents in the parabola `y^2=4a xdot` (a)which are inclined at an angle `theta` to each other. (b) Which intercept constant length `c` on the tangent at the vertex. (c) such that the area of ` A B R` is constant `c ,` where `Aa n dB` are the points of intersection of tangents with the y-axis and `R` is a point of intersection of tangents.