Bila x1 dan x2 akar-akar persamaann kuadrat 3x²-2x-8=0 maka nilai dari 1/x1 + 1/x2

3x^2-2x-8 = 0
Maka :
a = 3
b = -2
c = -8

x1+x2 = -b/a = -(-2)/3 = 2/3
x1x2 = c/a = -8/3

1/x1+1/x2
= x1+x2/x1x2
= 2/3 / -8/3
= -2/8
= -1/4