设f(x)=secx
则f(0)=1
(secx)'=secx tgx f '(0)=0
(secx)''=(secx)^3+secx(tgx)^2 f''(0)=1
则secx在x=0点展开的二阶泰勒公式为:
secx=f(0)+f'(0)x+(1/2)f''(0)x^2+o(x^2)
=1+(1/2)x^2+o(x^2)
原创 | 2022-10-12 02:39:16 |浏览:1.6万
设f(x)=secx
则f(0)=1
(secx)'=secx tgx f '(0)=0
(secx)''=(secx)^3+secx(tgx)^2 f''(0)=1
则secx在x=0点展开的二阶泰勒公式为:
secx=f(0)+f'(0)x+(1/2)f''(0)x^2+o(x^2)
=1+(1/2)x^2+o(x^2)