m

2=5，m=3

2. There must be two people who are the same, and there are four situations in * * * (refer to the power of the previous number).

-3ab^4

-3a^2b^3

-3a^3b^2

-3a^4b

3.-a/2=-5，a= 10

/n-3/= 10，

N-3= plus or minus 10

N= 13 or -7

4.6-2a=0，a=3

(Because it is a quadratic trinomial, that is, the third power of the first term does not exist, that is, its coefficient is 0)

5.2k=0，k=0

k？ - 1=0- 1=- 1

6.a

2=6，a=4

b

(5-a)

1=6，b=0

7.2

(n- 1)=5，n=4

a

1≠0，a≦- 1。