Tìm đạo hàm của các hàm số sau

$$\begin{gathered} a, y=x^2-x\sqrt{x}+1; b, y=\sqrt{2-5x-x^2} \\ c, y=\frac{x^3}{\sqrt{a^2-x^2}} ( a là hằng số ) d, y=\frac{1+x}{\sqrt{1-x}} \\ Giải \\ a, y\text{'}=2x-\frac{3}{2}\sqrt{x} \\ b, y\text{'}=\frac{-5-2x}{2\sqrt{2-5x-x^2}} \\ c, y\text{'}=\frac{3x^2\sqrt{a^2-x^2} -x^3\left(\sqrt{a^2-x^2}\right)}{a^2-x^2}=\frac{3x^2\sqrt{a^2-x^2}+x^3.{\displaystyle \frac{x}{\sqrt{a^2-x^2}}}}{a^2-x^2} \\ =\frac{x^2\left(3a^2-2x\right)}{\sqrt{{\left(a^2-x^2\right)}^3}} \\ d, y\text{'}=\frac{\sqrt{1-x}-\left(1+x\right).{\displaystyle \frac{\left(-1\right)}{2\sqrt{1-x}}}}{1-x}=\frac{2\left(1-x\right)+\left(1+x\right)}{2\sqrt{{\left(1-x\right)}^3}}=\frac{3-x}{2\sqrt{{\left(1-x\right)}^3}} \end{gathered}$$