[R] Help needed please

[Jaymin Shah]

I was wondering how to make a function which minimises  a vector (a,b,c,d).

I have an equation ( for simplicity) say its 5 -(3a+4b+6c+8d) and i want to make this equation as small as possible. Thus need to find the values for a b c and d for which this happens.  

I know there is a function in r which does minimisation but how could i make the function to input it into this function.

Thanks

Jaymin