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If f(x) = 3 sin x + 9 cos x, then f' (a) = 3 cos (x ) - 9 sin (x) f' (5) =Use the quotient rule to find the derivative of 4 sin (ac) + 2 5x4 + 4 You do not need to expand out your answer. Be careful with parentheses!Where, on the interval 0, 27], does the following function have a horizontal tangent line? f(x) = 16 sin (x) + 2x f (a) has horizontal tangents at a = Note: Answer in radians. Round answers to 4 decimal places.The height of a projectile (in meters) 9: minutes after it has been launched is given by f(a;) = 293 + 4si11(w) Find the velocity function, w = :] Find where on the interval from [0, 7r] the projectile has a velocity of zero, Use your previous answer to find the height of the projectile when its velocity is zero rounded to three decimal places