Adds two values together. Returns the result. :string+string Returns the second string attached to the end of the first string. The nspire uses & for this instead :value+list Adds value to every element of the list. :list+list If both lists are the same size, this adds each element of one list to the matching element of the other list. :matrix+matrix If both matrices are the same size, this adds each element of one matrix to the matching element of the other matrix.