I'm trying to save some CPU cycles in an application by finding a curve formula that's "very similar but simpler" than the ones I have. I'm wondering what the best way to do this in Wolfram Alpha is. I tried to split it up into a table and then run cubic fit on it but Alpha wasn't really having that.

Any suggestions?

Here are the two formulas I'm attempting to approximate:

plot 10^(((   (x*1.4+.3)^(.3)     )*128-128)/20) from x=0 to 1
plot 10^(((   (1-(x-.5))^.3     )*128-128)/20) from x=0 to 1

Here they are as tables:

Table[ 10^(((   (x*1.4+.3)^(.3)     )*128-128)/20) ,{x,0,1,.05}]
Table[ 10^(((   (1-(x-.5))^.3     )*128-128)/20)  ,{x,0,1,.05}]

And here's the syntax I tried.

quadratic fit[Table[ 10^(((   (1-(x-.5))^.3     )*128-128)/20)  ,{x,0,1,.05}]]

Here's what it looks like in Apple Grapher: