To differentiate you bring the power down and multiply it by any coefficients (numbers in front of the xs) then subtract one from the power
So x3 becomes 3x2
2x2 becomes 2*2x2-1 = 4x
4x becomes 4*1x1-1 = 4
7 is a constant so can't be differentiated
Final answer: 3x2 + 4x + 4