> ((twice square) 2)
16
> ((twice (twice square)) 2)
65536
> (((twice twice) square) 2)
65536
> (derive sin 0.0001)
#<procedure:...cheme/highorder.scm:18:2>
> ((derive sin 0.0001) 0)
0.9999999983333334
> ((derive sin 0.0001) 0)
0.9999999983333334
> (define 2* (derive square 0.0001))
> (2* 5)
10.000099999984968