How do you find the roots, real and imaginary, of y= (x-2)^2+(x-4)^2 using the quadratic formula?
1 Answer
Mar 3, 2016
Multiply out and simplify to find a quadratic in standard form, then apply the formula to find zeros
Explanation:
y=(x-2)^2+(x-4)^2
=(x^2-4x+4)+(x^2-8x+16)
=2x^2-12x+20
=2(x^2-6x+10)
This has zeros given by the quadratic formula:
x = (-b+-sqrt(b^2-4ac))/(2a)
=(6+-sqrt((-6)^2-(4*1*10)))/(2*1)
=(6+-sqrt(36-40))/2
=(6+-sqrt(-4))/2
=(6+-sqrt(4)i)/2
=(6+-2i)/2
=3+-i