dodge_viper 2017-7-3 10:02 PM
M2
請問（b)(ii)點做？
ppresent 2017-7-3 11:41 PM
consider the formula of (a), cos(x)^2 = [1+cos(2x)]/2,
Because cos(x) >= 0 for 0<=x<=pi/2,
we have cos(x/2) = sqrt((1+cos(x))/2) for 0<=x<=pi
Use the above formula for the case of n+1 in induction
[[i] 本帖最後由 ppresent 於 2017-7-3 11:43 PM 編輯 [/i]]
