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Math Functions

Required header:  #include <math.h>

C++ compilers offer basic mathematical functions.

Function Prototype Purpose
abs(x) int abs(int x); returns the absolute value of an integer.
fabs(x) double fabs(double x); returns the absolute value of a floating point number
ceil(x) double ceil(double x); rounds up to a whole number
cout<<ceil(11.2);
     
(prints 12)
(not normal rounding)
floor(x) double floor(double x); rounds down to a whole number
cout<<floor(11.5);
      (prints 11)
(not normal rounding)
hypot(a,b) double hypot(double a,
          double b);
calculates the hypotenuse (c) of a right triangle where a and b are the legs.
pow(x,y) double pow(double x,
         double y);
calculates x to the power of y.  If x is negative, y must be an integer.  If x is zero, y must be a positive integer.
pow10(x) double pow10(int x); calculates 10 to the power of x.
sqrt(x) double sqrt(double x); calculates the positive square root of x.
(x is >=0)
fmod(x,y) double fmod(double x,
         double y);
returns floating point remainder of x/y with same sign as x.  Y cannot be zero.  Because the modulus operator(%) works only with integers, this function is used to find the remainder of floating point number division.

<math.h>

 

 

NOTE:
The trigonometric functions work with angles in radians rather than degrees.

 All of the trigonometric functions take double arguments and have double return types. 

cos(x) cosine of x
sin(x) sine of x
tan(x) tangent of x
acos(x) arc cosine x
asin(x) arc sine of x
atan(x) arc tangent x
cosh(x) hyperbolic cosine of x
sinh(x) hyperbolic sine of x
tanh(x) hyperbolic tangent of x
exp(x) exponential function
log(x) natural logarithm
log10(x) base 10 logarithm