The space separated function call examples could do with a 2+ary example i think. How do you do something like pow(x+y,1/z)? I guess it must be "math pow x plus y 1 over z"? But then, the sqrt example has a level of nesting removed, and perhaps that's supposed to be generally the case, and actually it'd have to be "math pow a b" amd you need to set up a and b accordingly. I'm possibly just old fashioned and out of touch.