f'(x)=(x+ 1)(x+2)....((x+ 100)+x[(x+ 1)(x+2).....(x+ 100)]'

f'(0)= 1×2×3×....× 100+0×[(x+ 1)(x+2)....(x+ 100)]'|(x=0)

= 100!

The law of fractional division in which divisor is decimal;

1) First look at how many decimal places the divisor has, and then move the decimal point of the divisor by a few places to the right. If it is not enough, use zero to make up the digits.

2) Then divide by the fractional division of integer divisor.

Law of fractional division:

1) The numerator of the dividend is multiplied by the denominator of the divisor as the numerator.

2) The denominator of the dividend is multiplied by the numerator of the divisor as the denominator. (that is, the dividend is a constant, which is the reciprocal of multiplication and division)