更新1:
y = x^n sinx + n x^(n – 1) cosx Find dy/dx.
A question
回答 (1)
2009-05-04 8:22 pm
✔ 最佳答案
Make use of chain rule to do it.y = xn sinx + nxn-1 cosx
dy/dx = xn d(sinx)/dx + sinx d(xn)/dx + n[xn-1 d(cosx)/dx + cosx d(xn-1)/dx]
= xncosx + nxn-1sinx - nxn-1sinx + n(n - 1)xn-2cosx
= xncosx + n(n - 1)xn-2cosx
= xn-2(x2 + n(n - 1))cosx
參考: Physics king
收錄日期: 2021-04-19 14:16:30
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