Simple math vector class in C++

vec.h

#ifndef __VEC_HPP__
#define __VEC_HPP__

#include <iostream>
#include <cmath>

namespace vec
{
    typedef long double ld;
 
    class Vec // 2d
    {
    public:
        ld x, y;

        inline ~Vec() { x = y = 0; };
        Vec(const ld& x_, const ld& y_)
        {
            x = x_;
            y = y_;
        }

        inline ld mod() const { return sqrt(x*x + y*y); };

        inline bool operator==(const Vec& v) const { return x == v.x and y == v.y;  }
        inline bool operator!=(const Vec& v) const { return x != v.x or y != v.y; }
        inline bool operator>=(const Vec& v) const { return mod() >= v.mod(); }
        inline bool operator<=(const Vec& v) const { return mod() <= v.mod(); }
        inline bool operator>(const Vec& v) const { return mod() > v.mod(); }
        inline bool operator<(const Vec& v) const { return mod() < v.mod(); }

        inline Vec operator+(const Vec& v) const { return Vec(x + v.x, y + v.y); }
        inline Vec operator-(const Vec& v) const { return Vec(x - v.x, y - v.y); }
        inline Vec operator*(const ld& k) const { return Vec(k*x, k*y); }
        inline Vec operator/(const ld& k) const { return Vec(x/k, y/k); }
        inline ld operator*(const Vec& v) const { return x*v.x + y*v.y; }

        inline Vec operator+=(const Vec& v) { *this = *this + v; return *this; }
        inline Vec operator-=(const Vec& v) { *this = *this - v; return *this; }
        inline Vec operator*=(const ld& k) { *this = *this * k; return *this; }

        friend std::ostream& operator<<(std::ostream& out, const Vec& v) 
        {
            out << '(' << v.x << ',' << ' ' << v.y << ')';
            return out;
        }
    };
}

#endif