2x² + x - 3 = 0. This is a quadratic equation of the form:
ax² + b . x + c = 0, where:
a = 2
b = 1
c = - 3
To find the roots (or zeros) of this quadratic equation we have to apply the following formula:
x' = [- b + √(b² - 4.a.c)]/2a and x" = [- b - √(b² - 4.a.c)]/2a
Replace a , b and c by their respective values in both (x' and x")
x' = [-1 + √(1² - 4(2)(-3)]/2(2) and x" = [-1 - √(1² - 4(2)(-3)]/2(2)
x' = [-1 + √(1+24)]/4 and x' = [-1 - √(1+24)]/4
x' = (-1+5)/4 and x" = (-1 - 5)/4
x' = 4/4 and x" = -6/4
x' = 1 and x" = - 3/2
