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sara_87
Jan22-08, 05:13 PM
1. The problem statement, all variables and given/known data

I have to determine whether the following is a linear transformation

T(x,y)=(x,0)

2. Relevant equations



3. The attempt at a solution

again, let v=(v1, v2) and w=(w1,w2)

then, T(v+w)=T(v1+w1, v2+w2)=(v1+w1, 0)

and, T(v)+T(w)=(v1+w1, 0)
so the first condition holds.

AND:

let c be a constant:
T(cv)=T(cv1,cv2)=(cv1, 0)=c(v1,0)=cT(v)
so both conditions hold
therefore it's linear transformation
is that correct?

HallsofIvy
Jan22-08, 05:25 PM
You haven't said what x and y are! If they are real numbers, that is that T is a function from R2 to R2, then yes, those are exactly what you need to show. (Of course, taking c= 0 in the second shows T(0)= 0 and taking c= -1 shows T(-v)= -T(v) which are required by not necessary to prove separately.)

ircdan
Jan22-08, 05:26 PM
yea it is


edit: nevermind listen to halls, you do need to be more precise with this kind of thing probably