Respuesta :
f(x) = x^4 + 9x^2 = x^2(x^2 + 9) = x^2(x^2 - (-9)) = x^2(x - sqrt(-9))(x + sqrt(-9)) = x^2(x + 3i)(x - 3i)
Answer:
[tex]f(x)=x^2(x+3i)(x-3i)[/tex]
Step-by-step explanation:
Given expression is,
[tex]f(x)=x^4+9x^2[/tex]
[tex]=x^2\{x^2+9\}[/tex] ( Converse of distributive property )
[tex]=x^2\{x^2-i^2.9\}[/tex] ( i² = -1 )
[tex]=x^2\{(x)^2-i^2(3)^2\}[/tex]
[tex]=x^2\{(x)^2-(3i)^2\}[/tex]
[tex]=x^2(x+3i)(x-3i)[/tex] ( a² - b² = (a+b)(a-b) )
Since, further factorization is not possible,
Thus, the required linear factorization of the function is,
[tex]f(x)=x^2(x+3i)(x-3i)[/tex]
First option is correct.