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

7536 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Simplify the following expression: ( (x^5) / (x^2) ) ^ 4


Solve the following simultaneous equations for x and y. 2x+5y=9 and 4x-3y=7


Simplify fully [(256x^20)/(y^8)]^ (-1/4).


How do I solve an equation where there are unknowns on both sides of the equation?


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