private void button38_Click(object sender, EventArgs e)
{
String str = "Radians";
if (Radians.Checked)
{
str = "Radians";
}
else if (Grads.Checked)
{
str = "Grads";
}
else if (Degrees.Checked)
{
str = "Degrees";
}
calculadora.calcular_tangenteh(str);
textBox1.Text = calculadora.stream.textBox;
}