Need a function that can simplify an expression and it is string type.
For example, when using the polynomial function to calculate 4x^3 - 11x^2 + 2x + 3.
The actual roots are 3 roots, 3/4, 1-√2, and 1 +√2, while the function giving 3 correct values, 3/4, 8-(128^(1/2)/8, and 8+128^(1/2)/8; 1-√2 actually equals 8-(128^(1/2)/8; but needed to be simplified.