17/09/21 00:47:21.48 1RUtzMNA.net
>>208
sin(x) = x(1 - (x^2)/6 + O(x^4))
逆数とって
1/sin(x) = (1/x)*1/(1 - (x^2)/6 + O(x^4))
= (1/x)*(1 + (x^2)/6 + O(x^4))
ちなみに
1/(1 + ax + O(x^2)) = 1 - ax + O(x^2)
だからな。
17/09/21 00:47:21.48 1RUtzMNA.net
>>208
sin(x) = x(1 - (x^2)/6 + O(x^4))
逆数とって
1/sin(x) = (1/x)*1/(1 - (x^2)/6 + O(x^4))
= (1/x)*(1 + (x^2)/6 + O(x^4))
ちなみに
1/(1 + ax + O(x^2)) = 1 - ax + O(x^2)
だからな。