C++ being superset of C, supports large number of useful mathematical functions.

double sin(double) :

This function takes angle (in degree) as an argument and return its sine value that could be verified using sine curve.

double cos(double) :

This function takes angle (in degree) as an argument and return its cosine value that could be verified using cosine curve.

double tan(double)

This function takes angle (in degree) as an argument and return its tangent value. This could also be verified using Trigonometry as Tan(x) = Sin(x)/Cos(x).

double sqrt(double) :

This function takes number as an argument and return its square root value. Number can not be negative value.

int abs(int) :

This function takes integer number as an argument and return its absolute value. It means, the output will always be positive regardless of sign of input.

double pow(double, double)

This function takes one argument as base and other as exponent.

double hypot(double, double)

This function requires two sides of the right angled triangle to give output as its hypotenuse.

double floor(double)

This functions returns the integer value lesser or equal to argument passed in the function.

double fabs(double)

This function returns the absolute value of any number.

double acos(double)

This function returns the arc cosine of argument. The argument to acos() must be in the range -1 to 1 ; otherwise, a domain error occurs.

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