Pointer error in two lines of code

[T-Mix]

Hi everyone,
I'm typing up a program that allows the input of the radius and height of a cylinder and outputs the total surface area, lateral surface area, and volume of the cylinder. I've typed up the skeleton of the program and I'm just fixing up errors but I can't figure this one out. (The errors are pointed out to the right of the lines through comments in the bottom half of the program)

#include <iostream>
#include <cmath>
using namespace std;

double totalSurfaceArea(double r, double h);
double lateralSurfaceArea(double r, double h);
double volume (double r, double h);

int main()
{
double r, h;
double tArea, lArea, v;
const double PI = 3.14159265;

cout << "This program will calculate the total surface area, lateral surface area, and volume of a right-circular cylinder. \n Please enter the radius and height of the cylinder. \n";
cin >> r >> h;

tArea = totalSurfaceArea (r, h);
lArea = lateralSurfaceArea (r, h);
v = volume (r, h);

cout << "The total surface area is: " << tArea << "; the lateral surface area is: " << lArea << "; and the volume is " << v << ".";

std::cin.clear();
std::cin.ignore();
getchar();
return 0;
}
const double PI = 3.14159265;
double totalSurfaceArea (double r, double h)

{
double tArea;

tArea = 2*PI*r(r+h); //error is in the first r

return tArea;

}

double lateralSurfaceArea (double r, double h)
{
double lArea;

lArea = 2*PI*r*h;

return lArea;

}

double volume (double r, double h)
{
double v;

v = PI(pow(r,2))*h; //error is in the PI

return v;

}

The type of error is "term does not evaluate to a function taking 1 argument" in both cases, and if I hover over the 'r' or 'PI' the error says "expression must have (pointer-to-) function type." I am something of a novice programmer
in C++, so using simple terms is most helpful. Thanks in advance.
p.s. Apologies for the poor format copy/paste has left you)

[GCDEF]

r is a double, not a function. See how you're using the asterisk to indicate multiplication? You need to do that consistently. Parens are used to call functions, not to indicate multiplication.

[T-Mix]

Thank you for your help! I've got the program running now.