JavaScript Math.sin() is a static function that calculates the sine of a given angle in radians. The sine is a trigonometric function that represents the ratio of the opposite side’s length to the hypotenuse length in a right-angled triangle.
Syntax
Math.sin(x)
Parameter(s)
The variable x (in radians), whose sine value is to be determined.
Return Value
The sine value is between -1 and 1.
Note
- The sin() method returns NaN if the passed value is empty.
Example 1
The following code demonstrates the use of the sin() method.
let a = 0;
let b = 1;
let c = Math.PI;
let d = 2 * Math.PI;
let e = (Math.PI) / 2;
console.log(Math.sin(a));
console.log(Math.sin(b));
console.log(Math.sin(c));
console.log(Math.sin(d));
console.log(Math.sin(e));
Output
0
0.8414709848078965
1.2246467991473532e-16
-2.4492935982947064e-16
1
Example 2
The following example demonstrates the case where an empty value is passed.
let x;
console.log(Math.sin(x));
console.log(Math.sin());
Output
NaN
NaN
Example 3
The following code example demonstrates applying the Math.sin() method in a simple programming context.
Given the base angle of the triangle and the base side, find all the remaining sides of the triangle.
// Given the base angle of a triangle and the base side,
// find all the remaining sides of the triangle.
let p;
let b;
let h;
let angle;
const r = require('readline');
const rl = r.createInterface({
input: process.stdin,
output: process.stdout
});
const prompt1 = () => {
return new Promise((resolve, reject) => {
rl.question('Base side: ', (answer) => {
b = answer;
resolve();
});
});
};
const prompt2 = () => {
return new Promise((resolve, reject) => {
rl.question('Base angle(in radians): ', (answer) => {
angle = answer;
resolve();
});
});
};
const main = async () => {
await prompt1();
await prompt2();
rl.close();
console.log('The three sides of the triangle are:');
console.log(b); //base side
let angle2 = (Math.PI) / 2 - angle;
h = b / (Math.sin(angle2));
console.log(h); //hypotenuse
p = h * Math.sin(angle);
console.log(p); //third side
}
main();
Output
Test Case 1:
Base side: 6
Base angle(in radians): 0.523599
The three sides of the triangle are:
6
6.928204127882605
3.464103410351597
Test Case2:
Base side: 30
Base angle(in radians): 0.785398
The three sides of the triangle are:
30
42.42639993882793
29.99999019615471
Compatibility(Version and above)
- Google Chrome v1
- Internet Explorer v3
- Firefox v1
- Edge v12
- Opera v3
- Safari v1
- Android webview v1
- Chrome for Android v18
- Firefox for Android v4
- Opera for Android v10.1
- Safari on iOS v1
- Samsung Internet v1.0
- Node.js
JavaScript version: ECMAScript 1
That’s it.