1) f'(x) = 2*7*x^6 - 8 - 9
2) f'(x) = 3*(-7)/x^8 - 1/4 * 4 x^3 + 6/2sqrt(x)
3) f'(x) = cosx*(3x^4-1) + sinx*(12x^3)
4) f'(x) = (1*cosx - (x+3)*(-sinx))/ cos^2
5) f'(x) = 12x^3*(x+5) + (3x^4-1)*1
6) f'(x) = 4*(6x^3-2)^3 * 18x^2
7) f'(x) = -sin (3x + pi/4) *3
= 29 54/54 - 4 29/54 = 25 25/54
(412+116) - 112 = (412-112) + 116 = 416
(684+915) - 484 = (684-484) + 915 = 1115
1287 - (487+164) = (1287-487) + 164 = 964
971 - (235+371) = (971-371) + 235 = 835