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I'm trying to make a program that will compare the results in calculating the Cosine with powerseries method and Math.cos method. This is what i have.

```
import java.util.*;
class Cosine{
public static void main(String[] args){
int degrees = 0;
Scanner myScanner = new Scanner(System.in);
while(true){
System.out.println("Enter some integer value of degrees (-1 to quit)");
degrees = myScanner.nextInt();
if (degrees == -1)
{
break;
}
System.out.println("\nCosine calculation for "+ degrees +" degrees using...");
System.out.println(" ...Power Series: "+ myCos(degrees * Math.PI/180));// convert degrees to radians
System.out.println(" ...Math class: "+ Math.cos(degrees * Math.PI/180));//check result vs Math class
}
System.out.println("Have a nice day!");
}
private static double myCos(double radians) {
int expFact = 2;//the exponent & factorial term
double negationFactor = 1.0;// used to alternate between addition and subtraction of terms
double powerSeries = 0.0;//accumulator for power series
double factorialResult = 0.0;//result of the factorial
while (factorialResult < Double.POSITIVE_INFINITY) {// stop when factorialResult overflow is reached
factorialResult = factorial(expFact);// calculate the factorial
powerSeries = 1 +(negationFactor * (Math.pow(radians, expFact))/factorialResult);// the next statement calculates power series
negationFactor *= -1.0;// the negation factor alternates + - + - +.....
expFact +=2;//increment exponent and factorial term by two
}
return radians - powerSeries;//subtraction, as specified in the formula
}
//calculates the factorial
private static double factorial(int x) {
double f = (double) x;
for (int i= x-1; i>0; i--)
{
f = f*(double)i;
}
return f;
}
}
```