Question

If p and q be the roots of x square - 2 x minus 3 equal to zero then find the value of pq + q cube

Answer 1

$x^{2} - 2x - 3 = 0 \: is \: the given \: equation$
The roots can be calculated as follows-
x^2+x-3x-3=0
x(x+1)-3(x+1)=0
(x-3)(x+1)=0
x=3 or x=-1
Thus p=3, q=-1
Thus pq+q^3
=3*(-1)+(-1)^3
=-3-1
=4

Answer 2

The roots can be calculated as follows-

x^2+x-3x-3=0

x(x+1)-3(x+1)=0

(x-3)(x+1)=0

x=3 or x=-1

Thus p=3, q=-1

Thus pq+q^3

=3*(-1)+(-1)^3

=-3-1

=4