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. 

AI

Related Maths A Level answers

All answers ▸

Ignoring air resistance and assuming gravity to equal 9.81. If a ball of mass 1kg is dropped from a height of 100m, calculate it's final velocity before it hits the ground.


Maths C1 2017 1. Find INT{2x^(5) + 1/4x^(3) -5}


Express X/((X+1)(X+2)) in partial fractions. OCR C4 style question


Using logarithms solve 8^(2x+1) = 24 (to 3dp)