How do you find the roots, real and imaginary, of y= x^2 -3x -2(x+1)^2 using the quadratic formula?

1 Answer
Jun 8, 2016

(-7+-sqrt41)/2

Explanation:

y=x^2-3x-2(x+1)^2

= x^2-3x-2(x^2+2x+1)

= -x^2-7x-2

As according to quadratic formula roots of ax^2+bx+c=0 are

(-b+-sqrt(b^2-4ac))/(2a), roots of -x^2-7x-2 are

(-(-7)+-sqrt((-7)^2-4(-1)(-2)))/(2(-1))

= (7+-sqrt(49-8))/(-2)

= (-7+-sqrt41)/2