6) Use the chain rule to differentiate the following. a) f(x) = (5x2 + 11x)20 b) f (x) = tan(5x2) c) f(x) = [secx + tan x]5 7) Use implicit differentiation to find ax a) cos(y' ) + x = ex b) 6x3 + 7y3 = 13xy8) Find the derivatives of the following functions. a) (ex Inx) b) - [In(cos'x)] 9) Find the derivatives of the following functions. a) f(x) = sec-1 vx b) f (x) = csc 1(2x + 1) 10) Expanding rectangle. A rectangle initially has dimensions 2 cm by 4 cm. All sides begin increasing in length at a rate of 1 cm/s. At what rate is the area of the rectangle increasing after 20 s