**Here is some Working Rule on Angle between Curves ;**

1) If Equations of two curves are given . Find the value of

*fom the equation of two curves .*

**dy/dx**2) If the value of

*obtained from the two equations are equal then , angle between the curve is*

**dy/dx***degree i.e. they touch each other at each point i.e. the two curves are same .*

**0**If product of the values of

*for two curves is*

**dy/dx***then the two curves cut each other orthogonally (perpendicularly) .*

**-1,**3) If given condition (2) is not true , find the co-ordinates of the points of intersection of the two curves by solving the equation of the two curves .

Then find the values of

*from the equation of two curves at one point of intersection .*

**dy/dx**This will give gradient of the tangent to the two curves

i.e.

*and*

**m1***.*

**m2**Then find the angle

*between the curves by the formula*

**A**

**tanA= +and- [m1 -m2]/1 + m1m2 .**Do this fo every point of intersection .