some question about F.1 Maths

1) The constant term of a polynomial is the term of degree 0.
For example : x3 + 2x2 + 3x + 4
In here, +4 is the constant term that with degree 0.
x has a degree of 3, 2x has a degree of 2, 3x has a degree of 1
2) For example, in the expression 9x2, the coefficient of x2 is 9.
Find the coefficient of
(i) x4 → The coefficient of x4 is 1
(ii) x3 → The coefficient of x3 is 1
(iii) x2 → The coefficient of x2 is 1
3) In mathematics, a coefficient is a constant multiplicative factor of a certain object.
Example : The coefficient of 5x4 is 5.
4) 8xyz2 and −5xyz2 are like terms because they have the same variables and power while 3abc and 3ghi are unlike terms because they have different variables.
1.x,-3x
They have the same variable "x", so this is a pair of like terms.
2.2,-(1/2)x
They have the same variable "x", so this is a pair of like terms.
3.3xy,4yx
Since yx = xy, they have the same variable "xy", so this is a pair of like terms.
4.5x2y,5y2x
Since x2y = y2x, they have the same variable "xy", so this is a pair of like terms.
5.5xyz,9xzp
Since xyz is not equal to xzp, they don't have the same variable, so this is not a pair of like terms.
5) Subtract the sum of -6.5 and -2.4 from the sum of 3 and -4.
將 3 及 -4 的和減去 -6.5 及 -2.4 的和
[3 + (-4)] - [(-6.5) + (-2.4)]
= (3 - 4) - (-6.5 - 2.4)
= (-1) - (-8.9)
= -1 + 8.9
= 7.9
6) Solve the following equations :
1. 22 - 3x = 8x - 8
22 - 3x + 3x = 8x + 3x - 8 將兩面 + 3x
22 = 11x - 8
11x - 8 = 22
11x - 8 + 8 = 22 + 8 將兩邊 + 8
11x = 30
11x / 11 = 30 / 11 將兩邊 除 11
x = 30 / 11
得出的答案是分數，其實都是正確的！
2. - (25 / 4) = 5 / -2x
-25 / 4 x 4 = 5 x 4 / -2x 負號可以放在分子或分母, 將兩邊 x 4
-25 = 20 / -2x
-25 = -20 / 2x 可以將分母的負號放到分子去
-20 / -25 = 2x 可以將右邊的那個分子放到左邊那數當分子的
4 / 5 = 2x
2x = 4 / 5
2x / 2 = (4 / 5) / 2 將兩邊 除 2
x = 2 / 5
6) v2 divide a divide x--------why will be v2/ax(please explain)
v2 / a / x
= (v2 / a) / x
= (v2 / a) x (1/x) 要記得 除 x = 乘 1/x
= v2 / ax
7) (-8)4+?
係唔係打錯題目？
(-8)4 + ?
= 4(-8) + ?
= -( 4 x 8) + ?
= -32 + ?