The solve function with a single equation and a single variable uses the scalar solver. When called with a single argument, it is equivalent to solve(eqn, indets(eqn, name)).

The scalar solver reports all solutions found, even if some roots are multiple roots. For polynomials, the scalar solver finds all solutions.

For polynomials of degree 2, 3, and 4, the scalar solver computes the explicit solutions. For irreducible and non-decomposable polynomials of degree higher than 4, the scalar solver returns the solutions using RootOf notation.

For information on the return values of the solve command, see solve/details.

$\mathrm{solve}\left(\cos \left(x\right)+y=9\,x\right)$

$\mathrm{\pi }-\arccos \left(y-9\right)$

$\mathrm{solve}\left(x^3-6x^2+11x-6\,x\right)$

$1,2,3$

$\mathrm{solve}\left(\left\{x^3-6x^2+11x-6\right\}\,\left[x\right]\right)$

$\left[\left[x=1\right]\,\left[x=2\right]\,\left[x=3\right]\right]$