f'(x)=5[xsin(2x)+tan^4(x^7)]^4 times the derivative of the expression within the bracket. d/dx[xsin(2x)] =sin(2x)+2xcos(2x) --- (1) d/dx[tan^4(x^7)]=4tan^3(x^7).sec^2(x^7... =28x^6tan^3(x^7)sec^2(x^7) --- (2) f'(x)=5[xsin(2x)+tan^4(x^7)]^4 [ (1)+(2)]