Question

Algebra 2 help! Identify all of the real roots of
2x^3 -42x+40=0

Answer 1

2x^3-42x+40=0

// divide the left hand side by 2
x^3-42x+40= 0

// according to wolfram alpha the left side of the equation factors to
(x-4)(x-1)(x+5) = 0

//therefore
x = 4, x= 1, x = -5

Answer 2

Thank you so much Tomo!