is f:RR2,f(t)=(t2,t3)f:\mathbb{R}\rightarrow \mathbb{R}^2, f(t)=(t^2, t^3) an embedding?

MathNugget

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I am using this definition:
An embedding is a function f:MNf:M\rightarrow N, m=dim(M)n=dim(N)m=dim(M)\leq n=dim(N) (dim is dimension) that satifies rg(dxf)=m,xMrg (d_xf)=m, \forall x\in M (the differential is injective).

I suppose I have to calculate df1dt,df2dt\frac{df_1}{dt}, \frac{df_2}{dt}, with f(t)=(f1(t),f2(t))f(t)=(f_1(t), f_2(t)) ?
Also, rg here is the rank of the matrix... there supposedly should be a matrix I get out of this...
 
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I suppose I have to calculate df1dt,df2dt\frac{df_1}{dt}, \frac{df_2}{dt}dtdf1,dtdf2, with f(t)=(f1(t),f2(t))f(t)=(f_1(t), f_2(t))f(t)=(f1(t),f2(t)) ?

You suppose correctly. What is the resulting differential in your example?
 
You suppose correctly. What is the resulting differential in your example?
Wouldn't it be (2t,3t2)=(df1dt,df2dt)(2t, 3t^2)=(\frac{df_1}{dt}, \frac{df_2}{dt}). The rank would be 0 in 0... so it's not an embedding, innit?
 
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