The quadratic equation 2x^2 + 8x + 1 = 0 has roots a and b. Write down the value of a + b, a*b and a^2 + b^2.

Using Vieta's formulas, which make the correspondence between the sums and products of the roots of a polynomial and its coefficients, we can deduce that a + b = (-8)/2 = -4, ab = 1/2 =0.5 and a^2 + b^2 = (a+b)^2 - 2ab = (-4)^2 - 2*0.5 = 16 - 1 = 15. 

Answered by Andreea I. Maths tutor

5613 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

Integrate (x+2)/((x+5)(x-7)) using partial fractions between the limits 5 and -2, giving your answer to 3sf


Solve the differential equation dy/dx=(y^(1/2))*sin(x/2) to find y in terms of x.


Consider the function f(x) = 2/3 x^3 + bx^2 + 2x + 3, where b is some undetermined coefficient:


Find the value of 4!/0!


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences