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Maths help transformation

B8FC76E4-4A70-438D-9C06-80AFB1BFB138.jpg.jpeg
Can someone explain why iii) is f(2x)

I thought it would be f(1/2 x)
As that would be a stretch by scale factor 2 in the x direction and like twice as quick
Original post by Yazomi
B8FC76E4-4A70-438D-9C06-80AFB1BFB138.jpg.jpeg
Can someone explain why iii) is f(2x)

I thought it would be f(1/2 x)
As that would be a stretch by scale factor 2 in the x direction and like twice as quick


No it wouldnt be twice as quick.

Your transformation means that the signal finishes at t=2c now rather than t=c/2 which is what you want.

easy to check that f(1/2 * 2c) = f(c) = 0 so indeed your transformation makes this signal twice as long.
Original post by Yazomi
B8FC76E4-4A70-438D-9C06-80AFB1BFB138.jpg.jpeg
Can someone explain why iii) is f(2x)

I thought it would be f(1/2 x)
As that would be a stretch by scale factor 2 in the x direction and like twice as quick


For it to occur twice as quick (i.e. compressing the function along the x-axis) you want a scale factor of 1/2, hence f(2x).
Reply 3
Original post by ghostwalker
For it to occur twice as quick (i.e. compressing the function along the x-axis) you want a scale factor of 1/2, hence f(2x).


Ahhh I think I’m getting my facts mixed up T^T

Thanks tho that makes sense
Question uses t for horizontal axis and f(x) for vertical / everywhere else in the question even though they should use f(t) :facepalm:

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