matlab invalid expression issue

solar_cell = @(V_mp)  exp((q.*V_mp)./(kb.*T(k)))).*(1+((q.*V_mp)./(kb.*T(k))))-(exp((q.*V_OC)./(kb.*T(k))))
 

%i am being told "Invalid expression. When calling a function or indexing a variable, use parentheses. Otherwise, check for mismatched delimiters"

Answer 1

[madhan ravi]

solar_cell = @(V_mp)  exp((q.*V_mp)./(kb.*T(k))).*(1+((q.*V_mp)./(kb.*T(k))))-(exp((q.*V_OC)./(kb.*T(k))))

Answer 2

[Walter Roberson]

solar_cell = @(V_mp) exp((q.*V_mp)./(kb.*T(k)))) <-- too many ) at this point