hetifate

i am also an f.4 student , and this is my steps
1. you have to dy/dx  the u^10
2. so, the derivative is (10u^9) * (du/dx)  because we can calculate d(u^10)/dx and we have to use chain rule with the base "u"
3. after knowing the derivative is  (10u^9) * (du/dx), we can sub u= 3x^2 + 2 inside the answer and calculate the derivatives directely

Hope i can help you

hetifate

5 可以 直接 d(u^10)/dx, 因為個 上面系 u but not x

hetifate

只有 上面系 x (e.g. 2x*3...) 下面先可以用 dx