Find the derivative. I; d I 6t dt dx cos 0 a. by evaluating the integral and differentiating the result. b. by differentiating the integral directly. a. Evaluate the denite integral. 1/; d d 3 cos 6t dt = a (D) 0 (Simplify your answer. Use integers or fractions for any numbers in the expression.) Find the derivative of the evaluated integral. 4? d 6t dt = dx cos 0 (Simplify your answer. Use integers or fractions for any numbers in the expression.) b. Which ofthe following is the correct way to nd the derivative of the given integral directly? if} A. Use the Fundamental Theorem of Calculus, Part 1, with 1/; as lower limit and 0 as upper limit, and then use the chain rule of differentiation. B Use the Fundamental Theorem of Calculus, Part 1, with 0 as lower limit and I; as upper limit, and then use the chain rule of differentiation. C. Use the Fundamental Theorem of Calculus, Part 1, with 4/; as lower limit and 0 as upper limit, and then use the product rule of differentiation. D Use the Fundamental Theorem of Calculus, Part 1, with 0 as lower limit and f; as upper limit, and then use the product rule of differentiation. Differentiate the integral directly. I? d a costdt= D 0 (Simplify your answer. Use integers or fractions for any numbers in the expression.)