Q. 21. Find the L.C.M. of the polynomials: f(x) = 35 (x4 - 27x) and g(x) = 40 (2x35x2 - 3x). Q. 22. Find the L.C.M. of the polynomials: f(x) = 15x375x2 - 90x and g(x) = 6x4 - 18x3 - 108x Q. 23. The GCD and LCM of two polynomials are (x-7) and (x- 10x+ 11x+70). If one is (x - 5x-4), find the other. Q. 24. If (x + 3) (x - 2) is the HCF of the polynomials f(x) = (x + 3) (2x- 3x + p) and g(x) = (x-2) (3x+10x - q), find p, q. Q. 25. For what value of k the HCF of x+x-(2k + 2) and (2x + kx - 12) is (x + 4)? www Q. 26. Simplify the following rational expressions: (i) (x4 - 6x3 + 36x2)/(x3 + 216). (ii) (x4 - 1)/(x-1). Q. 27. Which rational expression should be subtracted from (2x + 2x - 7) / (x + x - 6) to get (x - 1)/(x-2). - Q. 28. Simplify: [(2x-1)/(x 1) - (x + 1) / (2x + 1) ] + [ (x - 1) / (x + 2) - (x + 1)/(x-2)]. Q. 29. If A = x - 7x+ 12 and B = x - 5x + 6, then evaluate the sum their reciprocals to the lowest form.