(a). Define the function f:

http://www.mathhelpforum.com/math-he...65ed088b-1.gif

by f(x,y) = (x+2y, 3x+4y). Is f one-to-one?

(Justify your answer)

can i answer this question like follow

x+2y=x+2y

x+y=x+y

3x+4y=3x+4y

x+y=x+y

?i know sounds stupid but this is all i can remember from the lecture.

anyone can give me some ideas? thanks^0^

one to one problem~~~... i mean