Question

Show that (x-5) is the factor of x^3-3x^2-4x-30

Answer 1

Answer:

put x=5 in given equation

5^(3)-3×5 ^(2)-4×5-30

=125-75-20-30

=0

therefore, (x-5) is a factor

Answer 2

Answer:

Let p(x) = x^3-3x^2-4x-30

Given, (x-5) is the zero of p(x).

When we equate (x-5) to zero, we get x as 5.

So, p(5) = (5)^3 - 3(5)^2 - 4(5) - 30

= 125 - 75 - 20 - 30

= 0

So, as the remaineder is zero, (x-5) is a factor of x^3-3x^2-4x-30.