Precalculus question

Question

Write f(x) = x3 + 25x in factored form. f(x) =

a. (x+25i)(x+1)(x–1)

b.(x+25)(x+i)(x–i)

c. x(x+5i)(x–5i)

d. x(x+5i)(x–5i)

Answer 1

x^3 + 25x =

x(x^2 + 25) =

x( x^2 - (-25)) =

x ( x + 5i) (x - 5i)

options C and D are the same and both are correct