what is the angle between:

and

Before I explain what causes me problems I'll show how far I managed to get..

1.The coordinates when the curves cross

from the first equation:

from the second equation:

I have 4 points..

2. The derivative of both curves

First curve:

Second curve:

Ok I'm not sure what to do now.. Was it even right to make out 8 k's?

after all.. k1 = k4, k2 = k3, k5 =k8, k6 = k7

I know that I have to use the following equation:

but I dunno which k's to put into equation..

The answer is supposed to be 51°