eturn a_trimmed;
    return a.toFixed(2);
}

function coefficient1(a, x) {
    a_trimmed = Number(a.toFixed(2));
    if (a_trimmed == 1)
        return x;
    if (a_trimmed == -1)
        return "-" + x;
    if (a_trimmed == 0)
        return "";
    return printable(a) + x;
}

function coefficient2(a, x) {
    a_trimmed = Number(a.toFixed(2));
    if (a_trimmed == 1)
        return " + " + x;
    if (a_trimmed == -1)
        return " - " + x;
    if (a_trimmed == 0)
        return "";
    if (a_trimmed > 0