If (a,b) is a are the coordinates of a point in Cartesian Plane, u is its magnitude and alpha is its angle then (a,b) in Polar Form is written as (u,alpha).
Magnitude of a cartesian coordinates (a,b) is given bysqrt(a^2+b^2) and its angle is given by tan^-1(b/a)
Let r be the magnitude of (-2,5) and theta be its angle.
Magnitude of (-2,5)=sqrt((-2)^2+5^2)=sqrt(4+25)=sqrt29=r
Angle of (-2,5)=Tan^-1(5/(-2))=Tan^-1(-5/2)=-68.198 degree
implies Angle of (-2,5)=-68.198 degree
But since the point is in second quadrant so we have to add 180 degree which will give us the angle.
implies Angle of (-2,5)=-68.198+180=111.802
implies Angle of (-2,5)=111.802=theta
implies (-2,5)=(r,theta)=(sqrt29,111.802)
implies (-2,5)=(sqrt29,111.802)
Note that the angle is given in degree measure.
