Is this the function you have to differentiate:
Maybe you should split up in terms and calculate the derivative of each term.
Do you know the derivative of a constant number? ...
Do you know this rule:
basically what i did was:
3x^-3=-9x^-4, times the 3 and -3 together and take away one power
same with 4 and 2, times them to get 8 and take away one power to get 8x.
so now i have dy/dx= -9x^-4+8x but i don't know if i keep the +1 or not?
Maybe you should talk with your teacher about this and take soms lessons, because I think it's really difficult to explain everything about calculating derivatives via the pc.
What have you learned yet at school about derivatives? ...