Solving a polynomial function using the solve function is not working

v1 = [1 -2 -5 6]

I need to store the polynomial function in a new vector: x^3 -2x^2 - 5x + 6 = 0

Did I do it correctly?

Secondly I need to solve the polynomial using the solve function, I tried to do it but it is not working

syms x3 x2 x1 
eqn = [x3 - 2*x2 - 5*x1 + 6 == 0]
solve(eqn)

Answer 1

[KSSV]

Read about roots

p = [1 -2 -5 6] ;
r = roots(p)

r = 3×1

-2.0000 3.0000 1.0000

Answer 2

[Torsten]

eqn = x^3 - 2*x^2 - 5*x + 6 == 0;
solve(eqn,'MaxDegree',3)