yang bisa tolong dong bantuannya....please pakai cara

[tex]a.3 {x}^{2} - 14x \\ b. \: {x}^{8} - {x}^{4} \\ c. \: 2ax + b \\ d. \: \frac{ \sqrt{x} - 4. \frac{1}{2} {x}^{ - \frac{1}{2} } }{x} = \frac{ \sqrt{x} - 2 {x}^{ - \frac{1}{2} } }{x} = \frac{1}{ \sqrt{x} } - \frac{2}{ \sqrt{ {x}^{3} } }[/tex]