Merge 2c7369782d into e067490424

02_Day_Data_types/02_day_data_types.md

@@ -57,12 +57,12 @@ In the previous section, we mentioned a little bit about data types. Data or val
 
 Primitive data types in JavaScript include:
 
- 1. Numbers - Integers, floats
+ 1. Numbers - integers, floats
- 2. Strings - Any data under single quote, double quote or backtick quote
+ 2. Strings - any data under single quote, double quote or backtick quote
  3. Booleans - true or false value
  4. Null - empty value or no value
  5. Undefined - a declared variable without a value
- 6. Symbol - A unique value that can be generated by Symbol constructor
+ 6. Symbol - a unique value that can be generated by Symbol constructor
 
 Non-primitive data types in JavaScript includes:
 
@@ -191,7 +191,7 @@ const PI = Math.PI
 console.log(PI)                            // 3.141592653589793
 
 // Rounding to the closest number
-// if above .5 up if less 0.5 down rounding
+// Round up if above 0.5, round down if less than 0.5
 
 console.log(Math.round(PI))                // 3 to round values to the nearest number
 
@@ -235,12 +235,14 @@ console.log(Math.log(10))       // 2.302585092994046
 console.log(Math.LN2)           // 0.6931471805599453
 console.log(Math.LN10)          // 2.302585092994046
 
-// Trigonometry
+// Trigonometry (the angle must be in radians)
+// If you want to use degrees, you have to first convert it to radians
+// Angle in radians = Angle in degrees x PI / 180
 Math.sin(0)
-Math.sin(60)
+Math.sin(1.05)
 
 Math.cos(0)
-Math.cos(60)
+Math.cos(1.05)
 ```
 
 #### Random Number Generator