<40 marks> 各位知識朋友 , 入黎幫我手 ar !!! ( 數學F.1 ) (66)

1. (4a - b³ + ab) - (b³ + a)

= (4a - b³ + ab) - b³ - a

= 4a - a- b³- b³+ ab

= 3a - 2b³ + ab



2a. The sequence is (-3)^m
Ans : -243

2b. the 100th term, that is m=100
(-3)^100
For any negative number with even number index, the number is positive
So Ans: 3^100


3. x/2 + 1 > x - 2
Put all unknowns to left, all number to right
x/2 - x > -2 -1
-x/2 > -3
Multipled by 2 on both sides
-x > -6
multipled by -1 on both sides. Since we multiple ( or divide) a negative number, so the inequilty sign must be changed
So x < 6