Question

x cube - 3x sq. - 9x -5​

Answer 1

Answer:

${x}^{3} - 3 {x}^{2} - 9x - 5 = 0$

by trail and error method

sub x= -1

the equation is statisfied

therefore -1 is a root of the equation

now convert cubic equation to quadratic equation

$( x + 1)( {x}^{2} - 4x - 5) = 0$

then the roots of quadratic equation. are

$(x + 1)(x - 5)(x + 1) = 0$

therefore the roots are -1. -1. 5