Sagot :
[tex]f(x)=2x^2+3x-4 \\ \\f(\sqrt{2})=2 \cdot (\sqrt{2})^2+3 \cdot \sqrt{2}-4 = 2\cdot 2+3\sqrt{2}-4=4+3\sqrt{2}-4=3\sqrt{2}[/tex]
[tex]f(x)=2x^2+3x-4\\\\f(\sqrt2)=2(\sqrt2)^2+3\sqrt2-4\\\\f(\sqrt2)=2*2+3\sqrt2-4\\\\f(\sqrt2)=4+3\sqrt2-4=3\sqrt2[/tex]