Write a C program to calculate the following Sum:
Sum=1-x²/2! +x⁴/4!-x⁶/6!+x⁸/8!-x¹⁰/10!

Description:

Write a C program to calculate the following Sum:   Sum=1-x²/2! +x⁴/4!-x⁶/6!+x⁸/8!-x¹⁰/10!

The above equation looks like a COSINE Equation of Taylor Sries i.e., 

Algorithm:

Step 1: Start
Step 2: Read x, n values as integers
Step 3: Set i = 2, s = 1, pwr = 1, nr = 1
Step 4: Convert x1 into degrees
Step 5: Assign x1 as sum
Step 6: while (i <= n)
         begin
             pwr ← pwr + 2;
             dr ← dr * pwr * (pwr - 1);
             sum ← sum + (nr DIV dr) * s;
             s ← s * (-1);
             nr ← nr * x1 * x1;
             i ← i + 2;
         end
Step 7: Print sum
Step 8: Stop

Program:

# include<stdio.h>
# include<conio.h>
# include<math.h>
void main()
{
 int i, n ;
 float x, val, sum = 1, t = 1 ;
 clrscr() ;
 printf("Enter the value for x : ") ;
 scanf("%f", &x) ;
 printf("\nEnter the value for n : ") ;
 scanf("%d", &n) ;
 val = x ;
 x = x * 3.14159 / 180 ;
 for(i = 1 ; i < n + 1 ; i++)
 {
  t = t * pow((double) (-1), (double) (2 * i - 1)) *
   x * x / (2 * i * (2 * i - 1)) ;
  sum = sum + t ;
 }
 printf("\nCosine value of sin %f is : %8.4f", val, sum) ;
 getch() ;
}

Input & Output:

Enter the Value of x: 2
Enter the limit of n: 4
The sum of sin 2.000000 series is 0.9994

Viva Questions:

Q: What is function ?

Ans: A function is a sub program it returns a value.

Q: What is procedure ?

Ans: A procedure is a sub program it does not returns a value.

Q: What are the basic data types in C ?

Ans: int, char, float, double.

Q: How to define preprocessor ?

Ans: By using the # symbal Ex: #include<stdio.h>.