97金門國中數學[第41.47.48題]
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Re: 97金門國中數學[第41.47.48題]
第 41 題
ABC = I
AB = C^(-1)
等號兩邊同乘 C
CAB = I
CA = B^(-1)
等號兩邊同乘 B
BCA = I
第 47 題
x ≧ 0,f(x) = x^7
x < 0,f(x) = -x^7
x > 0,f'(x) = 7x^6
x < 0,f'(x) = -7x^6
易知 f'(0) = 0
x > 0,f''(x) = 42x^5
x < 0,f''(x) = -42x^5
易知 f''(0) = 0
......
x > 0,f^(6)(x) = (7!)x
x < 0,f^(6)(x) = -(7!)x
易知 f^(6)(0) = 0
x > 0,f^(7)(x) = 7!
x < 0,f^(7)(x) = -7!
此時 f^(7)(0) 不存在,n 之最大整數值為 6
第 48 題
f(1) = 2
f^(-1)'(2) = 1/f'(1) = 1/5
ABC = I
AB = C^(-1)
等號兩邊同乘 C
CAB = I
CA = B^(-1)
等號兩邊同乘 B
BCA = I
第 47 題
x ≧ 0,f(x) = x^7
x < 0,f(x) = -x^7
x > 0,f'(x) = 7x^6
x < 0,f'(x) = -7x^6
易知 f'(0) = 0
x > 0,f''(x) = 42x^5
x < 0,f''(x) = -42x^5
易知 f''(0) = 0
......
x > 0,f^(6)(x) = (7!)x
x < 0,f^(6)(x) = -(7!)x
易知 f^(6)(0) = 0
x > 0,f^(7)(x) = 7!
x < 0,f^(7)(x) = -7!
此時 f^(7)(0) 不存在,n 之最大整數值為 6
第 48 題
f(1) = 2
f^(-1)'(2) = 1/f'(1) = 1/5