function doit() {
form.input.value = eval(form.input.value)
}

function Cos() {
x = form.input.value
if (x == '') alert('Error: Input Required');
else form.input.value = Math.cos(x);
}

function Sin() {
x = form.input.value
if (x == '') alert('Error: Input Required');
else form.input.value = Math.sin(x);
}

function Ln() {
x = form.input.value
if (x == '') alert('Error: Input Required');
else form.input.value = Math.log(x);
}

function Root() {
x = form.input.value
if (x == '') alert('Error: Input Required');
else form.input.value = Math.sqrt(x);
}

function Tan() {
x = form.input.value
if (x == '') alert('Error: Input Required');
else form.input.value = Math.tan(x);
}

function Icos() {
x = form.input.value
if (x == '') alert('Error: Input Required');
else form.input.value = Math.acos(x);
}

function Isin() {
x = form.input.value
if (x == '') alert('Error: Input Required');
else form.input.value = Math.asin(x);
}

function Itan() {
x = form.input.value
if (x == '') alert('Error: Input Required');
else form.input.value = Math.atan(x);
}

function Round() {
x = form.input.value
if (x == '') alert('Error: Input Required');
else form.input.value = Math.round(x);
}

function Ran() {
x = form.input.value
form.input.value = Math.random(x);
}

function Neg () {
x = form.input.value
if (x == '') alert('Error: Input Required');
else x = parseFloat(x) * -1;
}

function del() {
x = form.input.value
x = (x.substring) - 1
}