Show that the function f(x) = x^2 + 2x + 2 is always positive for real values of x

By completing the square we find that f(x) = x2 + 2x + 2 = (x+1)2 + 1Since (x+1)2 is a number that has been squared, it must be greater than or equal to zero. Therefore, f(x) = (x+1)2 + 1 must be greater than zero because adding a positive number to a number that is greater than or equal to zero will always give a positive number.

BC
Answered by Bradley C. Maths tutor

7080 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

If a curve has equation y=(4/3)x^3-2x^2-24x+16, find dy/dx and find the coordinates of the turning points.


Factorise x^2 - x - 6


How do I solve simultaenous equations? e.g. 2x -5y =11 and 3x+2y=7


How do I find the equation of a line that's perpendicular to another one?


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:

© 2026 by IXL Learning