[tex]a) \ f(x) = (x+1)(x-3)\\\\(x+1)(x-3) = 0\\\\x+1 = 0 \ \vee \ x-3 = 0\\\\x = -1 \ \vee \ x = 3\\\\\boxed{x \in\{-1,3\}}[/tex]
[tex]d) \ f(x) = 2^{17}x-8^{6}\\\\2^{17}x - 8^{6} = 0\\\\2^{17}x = 8^{6}\\\\2^{17}x = (2^{3})^{6}\\\\2^{17}x = 2^{18} \ \ /:2^{17}\\\\\boxed{x = 2}[/tex]
[tex]d) \ f(x) = \pi ^{2}x - 2\pi\\\\\pi^{2}x - 2\pi = 0\\\\\pi^{2}x = 2\pi \ \ /:\pi^{2}\\\\\boxed{x = \frac{2}{\pi}}[/tex]
