1.8 (a) Let heta be a nonzero angle and b a translation vector in the plane. Give a geometric
construction for a point PinE^(2) such that
Rot(O, heta )(P)=Trans(-b)(P).
[Hint: draw a picture, to find points P,Q with b=vec(QP) such that O is on the
perpendicular bisector of PQ and /_(P)OQ= heta .]
(b) By solving linear equations, find x,y such that
A([x_(1)],[x_(2)])+([b_(1)],[b_(2)])=([x_(1)],[x_(2)]), where ,A=([cos heta ,sin heta ],[sin heta ,-cos heta ]).
(c) Express the motion T:E^(2)->E^(2) defined in coordinates by T(x)=Ax+b in the
form T=Rot(P, heta ).
(d) Relate (a) and (b).
1.8
(a) Let 6 be a nonzero angle and b a translation vector in the plane. Give a geometric construction for a point P e E2 such that
Rot(O,0)(P)= Trans(-b)(P).
[Hint: draw a picture, to find points P, Q with b = QP such that O is on the perpendicular bisector of P Q and ZP O Q = 0.] (b) By solving linear equations, find x, y such that
(cos 0 sin 0
sin 0
where A
-cose
(c) Express the motion T : E2 > E2 defined in coordinates by T (x) = Ax + b in the form T = Rot(P,0).
d) Relate (a) and (b).