Write an equation with the leading coefficient 1, that has the following roots: -3i,4

Answer 1

Imaginary roots always come in pairs, so if -3i is a root, so is 3i. This means you have at least three factors

y = (x - 4)(x -3i)(x+3i) Multiplying the last two factors you have

y = (x-4)(x² + 9) foil this and you have

y = x³ - 4x² + 9x - 36