Re: [微積] 微積分的問題
※ 引述《ballballking (蛋蛋王)》之銘言：
: (3) 求x^(2/3)+y^(2/3)=1 的周長
y = [1 - x^(2/3)]^(3/2)
y' = (3/2)√[1 - x^(2/3)](-2/3)x^(-1/3)
√[1 + y'^2] = √[1 + (1 - x^(2/3))/x^(2/3)]
= x^(-1/3)
1
S = 4 ∫ x^(-1/3) dx
0
= 4 (3/2) = 6
如果只允許x^(2/3)裡的x為正
(3/2)就不要乘以4
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07/27 13:10, , 1F
07/27 13:10, 1F
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