QUESTION 9 If dx 3x - = k tan - 1 + C. what is the value of k? 9x - + 16 4 O 1/4 O 1/3 O 1/12 O 1/7 O none of the given choices here QUESTION 10 What must be the value of k in the EXACT differential equation ( 2 4 5x) dx + (6v2+ 2xte2 ) dy = 0?QUESTION 13 x cos x dx ? O x cos x + sin x + C O x sin x + cos x + C O x sin x + sin x + C x cos x + cos x + C O none of the given choices here QUESTION 14 In (x4) What is lim x-12(x-1)QUESTION 15 dx If =f (x) + C, f(x) =_? 1 - 4x2 O 1 - tan -1 (2x ) 2 tan -1 (2x) O - sin - (2x ) 2 O sec - (2x ) 2 O none of the given choices hereQUESTION 16 A Let f(x) and g(x) be the factors of 3 _ . If dx = + dx, how should the numerator of the second f (x) g (x) fraction in the integrand on the right side of the equation be represented? O Bx + C where B and C are constants O B where B is a constant Bx2 + Cx + D where B, C and D are constants O1 O none of the given choices here