solve.nb     pt, dicembre 1994 (rev. dicembre 2002)

Solve

Solve[4 - (x^2) == 0, x]

Solve[4 - (x^2) == 0, 
        x][[1]]

(x^2) /. Solve[4 - (x^2) == 0, 
          x][[1]]

N[Solve[{x1 + x2 == 1, 2 x1 - x2 == -5}, {x1, 
            x2}][[1]]]

Solve[{x1 + x2 == a, c x1 - x2 == b}, {x1, 
          x2}][[1]]

Solve su matrici

m = {{1 - z1, 2, 3}, {4, z2, 6}, {-1, -2, 9 z3}}; 
    MatrixForm[m]

v1 = {{1}, {2}, {3}}; MatrixForm[v1]

v2 = {{1, 2, 3}}; MatrixForm[v2]

v3 = {1, 2, 3}; MatrixForm[v3]

MatrixForm[m . v1]

MatrixForm[m . v2]

MatrixForm[m . v3]

Solve[
        m . v3 == 0, {z1, z2, 
          z3}][[1]]