What is wrong sin cos not wark

Question

import java.lang.Math;
import java.util.Scanner;
public class calculater {
public static void main(String[ ] args) {
Scanner input=new Scanner (System .in);
System .out.println ("Enter 1st num");
int a=input.nextInt();
System .out.println ("Enter 2st num");
int b=input.nextInt();
System .out.println ("Enter operation");
String op=input.next();
//int z;
if(op.equals("+")){
System.out.println(a+b);
}

else if(op.equals("-")){
System.out.println(a-b);
}
else if(op.equals("*")){

System.out.println(a*b);
}
else if (op.equals("/")){
System.out.println(a/b);
}
else if (op.equals("sin")){

System.out.println("sin =" +Math.sin(num));
}
else if (op.equals("cos")){

System.out.println("cos =" +Math.cos(num));
}
else if (op.e

Answer 1

( 1 )
Seems like your 'num' variable is missing and not defined (In this fix, I just added a temporary 'num' value because I dont exactly know what 'num' would you want)

( 2 )
Scanner input=new Scanner (System. in);
// should be
Scanner input=new Scanner (System.in);
// to read input properly.

If this is still unclear, please feel free to ask. Thanks.

https://code.sololearn.com/ca25a8a4A81A

Answer 2

You're likely expecting it to interpret your angle using degree units. It actually interprets the angle in radians. You can convert like this:
Math.sin(numDegrees * Math.PI / 180);

You could do something like this:
import java.util.Scanner;
public class calculater {
private static boolean isOneOperandOperation(String op) {
return op.equals("sin") || op.equals("cos") || op.equals("tan");
}

public static void main(String[ ] args) {
Scanner input=new Scanner (System .in);
System .out.println ("Enter 1st num");
int a=input.nextInt();

System .out.println ("Enter operation");

String op=input.next();
if (isOneOperandOperation(op)) {
// convert a from degrees to radians.
double angleInRadians = a * Math.PI / 180;
if (op.equals("sin"))
System.out.println(Math.sin(angleInRadians));
else if (op.equals("cos"))
System.out.println(Math.cos(angleInRadians));
else
System.out.println(Math.tan(angleInRadians));
}
else {
System.out.println ("Enter 2stnum");
int b=input.nextInt();

if(op.equals("+")){
System.out.println(a+b);
}
else if(op.equals("-")){
System.out.println(a-b);
}
else if(op.equals("*")){
System.out.println(a*b);
}
else if (op.equals("/")){
System.out.println(a/b);
}
}

}
}

Answer 3

Can you please tell me how you are gonna give input for sin and cos?

Answer 4

I remember that we should convert num to radians
a=60;
num= Math.toRadians(a);
System.out.println(Math.sin(num));