Question

Solve the equation: 3x² – 8x – 1 = 0 for x.

Answer 1

Given quadratic equation is: 3x² – 8x – 1 = 0 

On comparing the above equation with ax² + bx + c = 0, we get

a = 3, b = –8 and c = –1

Solution of x is x = `(-b +- sqrt(b^2 - 4ac))/(2a)` 

= `(-(-8) +- sqrt((-8)^2 - 4(3)(-1)))/(2 xx 3)`

= `(8 +- 2sqrt(19))/6`

= `(4 +- sqrt(19))/3`

∴ x = `(4 + sqrt(19))/3` and x = `(4 - sqrt(19))/3`