[tex]f:\mathbb{R}\rightarrow\mathbb{R},f(x)=3 {x}^{4} + 2 {x}^{2} + 1[/tex]
[tex]f \: para < = > f( - x) = f(x)[/tex]
[tex]3 \times {( - x)}^{4} + 2 \times {( - x)}^{2} + 1 = 3 {x}^{4} + 2 {x}^{2} + 1[/tex]
[tex]3 \times {( - 1 \times x)}^{4} + 2 \times {( - 1 \times x)}^{2} + 1 = 3 {x}^{4} + 2 {x}^{2} + 1[/tex]
[tex]3 \times {( - 1)}^{4} \times {x}^{4} + 2 \times {( - 1)}^{2} \times {x}^{2} + 1 = 3 {x}^{4} + 2 {x}^{2} + 1[/tex]
[tex]3 \times 1 \times {x}^{4} + 2 \times 1 \times {x}^{2} + 1 = 3 {x}^{4} + 2 {x}^{2} + 1[/tex]
[tex]3 {x}^{4} + 2 {x}^{2} + 1 = 3 {x}^{4} + 2 {x}^{2} + 1 \: (A)[/tex]
[tex] = > f \: para[/tex]
