(C)'=	0
(x^n)'=	nx^n-1
(x)'=	1
(a/x)'=	-a/x^2
(sqrt(x))'=	=1/[2sqrt(x)]
(a^x)'=	a^xln a
(e^x)'=	e^x
(log,a'x)'=	1/xln a
(ln x)'=	1/x
(sin x)'=	cos x
(cos x)'=	-sin x