幫我解答~ =) 20點

1.
log2(1/2) + log2(2/3) + log2(3/4)
= log2[(1/2)•(2/3)•(3/4)]
= log2(1/4)
= log2(2)^-2
= -2log2(2)
= -2


2.
f(x) = 2x² + 3x + k 能被 x + 1 整除，
f(-1) = 0
2(-1)² + 3(-1) + k = 0
2 - 3 + k = 0
k = 1


3.
x² + 5x + 2 = 0
x = {-5 ±√[(5)² - 4(1)(2)]}/2
x = (-5 + √17)/2 或 x = (-5 - √17)/2


4.
(6x² + 4x + 6) + (6x³ + 10x + 1)
= 6x² + 4x + 6 + 6x³ + 10x + 1
= 6x³ + 6x² + 14x + 7

2010-04-04 08:07:59 補充：
^ 代表次方。
例如 3^2 = 3² = 9