hey i know how to do it but the thing it i dont know how to find the x^3 + 3x -4 = 0 how do you simplify that to find the x - values ?
It should be clear by inspection that x = 1 satisfies the equation. Therefore x - 1 is a factor of x^3 + 3x - 4 and anyone studying calculus should be able to factorise a cubic if a linear factor is known and therefore establish that x = 1 is the only real solution.