十万里加急！！！ 高中数学题！！！！！ 求助 大神， 希望有高人 耐心指点， thx 希望　我能早早的　被　贵人　找到！ 因为 本人 打速成 很慢， 所以都用 拼音。?

求解下题 并 提供 列式, 列式，因为这很重要， 能解说一下更好
Question No.2

(Supplementary Exercise 6 , Integrated Questions (cross chapters) , 48, 49,50， (level 2)47,46, 45,43(b), 41(a), 36， 33)

48. Let f(x) be a quadratic polynomial, where the coefficient of x(2次方) is 1. It is given that 2 and -4 are the roots of the equation f(x)=0.

(a) Find f(x). (model ans: x(2次方)+2x - 8)

(b) Find the remainder when f(x) is divided by x+5. (model ans:7)

49. The graph of a quadratic function y=f(x) passes through (1,5).

(a) Find the remainder when f(x) is divided by x-1. (model ans: 5)

(b) It is given that the quotient is x-3 when f(x) is divided by x-1.

(i) Find f(x). (model ans: x(2次方)-4x+8)

（ii）Using the method of completing the square, find the coordinates of the vertex of the graph of y=f(x). （model ans: (2,4)）

50. (a) Find the remainder of ( x(3次方)+12（3次方）) / (x+10).
(model ans: 728)

(b) Let n and A be positive integers. In the figure, two solid metal cubes of sides n cm and 12 cm respectively are melted and recast into a solid metal cuboid. The height of the metal cuboid is (n + 10) cm and its base area is A cm(2). Using the result of (a) , find the greatest value of n. (model ans:718)
资料 已经 全提供了， figure 就 不 画出来了（也画不出）。