[solved]

Hi there, could do with some help/pointers/answers on this question:

L(1) and L(2) be the lines of E2, with L(1): y=d and L(2) (cos(z))y=(sin(Z))x, where z is a fixed angle between 0 and pi and d belongs to R.

1.write down the reflections R(1),R(2) in L(1) and L(2) in the form x--> Ax+b

2.Calculate the composite motion R(2)oR(1) in this form.

3.Using the fact that both R(1) and R(2) fix the point;

P=L(1)intersectionL(2)=((cot(z)d,d),

describe the effect of R(2)oR(1) on E2 in geometric terms.

Thanks a lot