MHB What is the complex number C for the transformation T?

AI Thread Summary
The transformation T maps points in the plane by multiplying them with a complex number C, expressed as C = a + ib. For the point A = (14, 1), the transformation yields T(A) = (34, -112), leading to the equation (a + ib)(14 + i) = 34 - 112i. The discussion emphasizes determining the values of a and b that satisfy this equation, which involves understanding the effects of rotation and scaling on the smaller house to achieve the larger one. The transformation involves both a counterclockwise rotation and an expansion factor, although these specifics are not provided. Ultimately, the goal is to find the complex number C that accurately represents the transformation.
avyunker
Messages
4
Reaction score
0
The transformation T maps the plane onto itself by multiplication by a complex number. That is, there is a complex number C=a+ib such that for any point P(x,y), T(P) is the point corresponding to the complex number C⋅P. For a particular complex number C the transformation T takes the smaller house in the diagram to the larger one. The point A=(14,1) ( the upper left corner of the window) on the smaller house is taken to the point T(A)=(34,-112) on the larger house.

The complex number C=?

The small house is rotated ? degrees counterclockwise and expanded by a factor of ?
 
Mathematics news on Phys.org
avyunker said:
The transformation T maps the plane onto itself by multiplication by a complex number. That is, there is a complex number C=a+ib such that for any point P(x,y), T(P) is the point corresponding to the complex number C⋅P. For a particular complex number C the transformation T takes the smaller house in the diagram to the larger one. The point A=(14,1) ( the upper left corner of the window) on the smaller house is taken to the point T(A)=(34,-112) on the larger house.

The complex number C=?

The small house is rotated ? degrees counterclockwise and expanded by a factor of ?

You need to work out a complex number (C = a + i b) such that (a + i b)(14 + i) = 34 - 112i.
 
Seemingly by some mathematical coincidence, a hexagon of sides 2,2,7,7, 11, and 11 can be inscribed in a circle of radius 7. The other day I saw a math problem on line, which they said came from a Polish Olympiad, where you compute the length x of the 3rd side which is the same as the radius, so that the sides of length 2,x, and 11 are inscribed on the arc of a semi-circle. The law of cosines applied twice gives the answer for x of exactly 7, but the arithmetic is so complex that the...
Is it possible to arrange six pencils such that each one touches the other five? If so, how? This is an adaption of a Martin Gardner puzzle only I changed it from cigarettes to pencils and left out the clues because PF folks don’t need clues. From the book “My Best Mathematical and Logic Puzzles”. Dover, 1994.
Back
Top