







A trig identity 
20130104 

Tehmas pose la question : Prove sinC+sinD=2sin(C+D/2)cos(CD/2) Harley Weston lui répond. 





2 + f(x) and f(x) + 2 
20111121 

Beth pose la question : Do you do y=2+f(x) the same way as if the 2 came after the equation such as y=f(x) +2 when graphing? Penny Nom lui répond. 





Reflection in the line y = x 
20100721 

tousif pose la question : Find the 2 x 2 matrix which represents a reflection in the line y = x?
Please help.... Penny Nom lui répond. 





The graph of f(x)=1/x 2 
20091129 

Kapilan pose la question : Please answer the following question:
Sketch the graph of f(x)=1/x 2 Harley Weston lui répond. 





Transformations 
20090204 

Vickie pose la question : Hello,
My daughter had a question on her
Week By Week about transformations and I can't remember what transformations
will result in proportional figures. If a transformation looks like it is smaller
what is that called? Also if the figure looks bigger what is that called?
Vickie Robert Dawson lui répond. 





Transformations and compositions 
20071129 

mary pose la question : Is there any possible relationship between composite functions and the concept of function transformations? Harley Weston lui répond. 





A rotated rectangle 
20070416 

Graham pose la question : There is a circle inside which from the centre to the top is a rectangle. Size is unimportant.
If I the rectangle is at 0 degrees and I know the coordinates of the 4 corners I can do a check to see
whether a given point x,y is inside the rectangle or not.
Question : If the rectangle is rotated by 50 degrees how do I check then as the lines of the rectangle are not
perfectly straight with regards to x and y ie at 0 degrees x changes but y is constant and vice versa.
At 50 degrees x and y change together. Penny Nom lui répond. 





Prove that a rhombus' diagonals are perpendicular 
20051002 

Tania pose la question : How do you prove that a rhombus' diagonals are perpendicular using the 2 column proof method? Walter Whiteley lui répond. 





A torus and a sphere 
20050327 

Tony pose la question : Is it possible to shrink a torus into a sphere? Andrei Volodin and Penny Nom lui répond. 





A sequence of transformations 
20050103 

Abraham pose la question : Please go to this web site and look at number 31.
http://www.nysedregents.org/testing/mathre/matharch/mathbtestau02.pdf
That is the New York state education web site.
Can you tell me if my answer would be marked correct? My answer was Transformation of 4,3 (T 4,3) followed by a reflection in the xaxis.If I graphed the question and wrote that, would I get full credit Harley Weston lui répond. 





Transformations of pattern blocks 
20030206 

Cheryl pose la question : I am trying to help my 8th grade son with Transformations  use of patttern blocks. He has to trace a figure and reflect it across the xaxis, which I can do, but then it indicates include ordered pairs  that confuses me. Penny Nom lui répond. 





Polar coordinates 
20000224 

Tran Trung pose la question : How do I convert r = 2/(2sin(theta)  3cos(theta)) to rectangular and x^{2} + y^{2} 2y = 0 to polar form? Harley Weston lui répond. 





Shapepreserving transformations 
19990504 

J McAndrew pose la question : A shape preserves its shape if a rotation, translation or scaling is performed on it. Are these the only continuous transformations which have this property? These transformations if performed on the parts and then summed have the same effect as the transformation being applied to the whole; are these linear transformations? Who, and what area of mathematics has classified all transformations of this type completely? Chris Fisher lui répond. 

