The equation 2x^2 + 2kx + (k + 2) = 0, where k is a constant, has two distinct real roots. Show that k satisfies k^2 – 2k – 4 > 0

Two distinct real roots means that we can use b^2-4ac>0 relationship for any ax^2+bx+c equation. Apply the above gives, 4k^2 - 42(k+2)>0 Simplifying gives, k^2 - 2k -4 >0

AT
Answered by Andreas T. Maths tutor

11996 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

Find the gradient of y=x^2-6x-16 at the point where the curve crosses the x-axis


Express 3cos(x)+4sin(x) in the form Rsin(x+y) where you should explicitly determine R and y.


f(x) = (sin(x))^3. What is f'(x)


The gradient of the curve at A is equal to the gradient of the curve at B. Given that point A has x coordinate 3, find the x coordinate of point B.


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2025 by IXL Learning