IIT JEE , AIEEE Forum - Mathematics , Analytical Geometry

joyfrancis

Hi.

See fig

since it is rotated about B the line formed after rotation will still have the point B on it.

The initial slope of the line is 1

so the angle which the initial line (b4 rotation) makes with the x axis is 45

By the fig. you will see that the final angle which the line (after rotation) makes with the x axis is 45+15=60

.: slope of the new line is tan60=root3

hence by point slope form equation is

y = xroot3+2-7root3