2 files changed, 11 insertions, 1 deletions
diff --git a/src/input.rs b/src/input.rs
index 4aae623..1dde8d5 100644
--- a/src/input.rs
+++ b/src/input.rs
@@ -59,6 +59,16 @@ impl Calculator {
                     *f = f.sin();
                 }
             }
+            "cos" => {
+                if let Some(f) = self.stack.last_mut() {
+                    *f = f.cos();
+                }
+            }
+            "tan" => {
+                if let Some(f) = self.stack.last_mut() {
+                    *f = f.tan();
+                }
+            }
             _ => {
                 if self.input_buffer.len() > 0 {
                     self.stack.push(self.input_buffer.parse::<f64>().unwrap());
diff --git a/src/ui.rs b/src/ui.rs
index 7222935..dd3bfc5 100644
--- a/src/ui.rs
+++ b/src/ui.rs
@@ -17,7 +17,7 @@ use crate::Calculator;
 
 const WIDTH: u16 = 32;
 
-const FUNCTIONS: [&str; 1] = ["sin"];
+const FUNCTIONS: [&str; 3] = ["sin", "cos", "tan"];
 
 impl Calculator {
     pub fn draw<B: Backend>(&self, f: &mut Frame<B>) {