Di bantu yah [tex]f(x) = (x + 1)( {x}^{3} + 2x + 1)[/tex]

[tex]f(x) = (x + 1)( {x}^{3} + 2x + 1) \\ f(x) = {x}^{4} + {2x}^{2} + x + {x}^{3} + 2x + 1 \\ f(x) = {x}^{4} + {x}^{3} + {2x}^{2} + 3x + 1 \\ [/tex]
jika soalnya seperti diatas..tidak ada perintah lain..maka jwbnnya seperti diatas