1-9/41a^3n-2 b^2n+3是六次單項式,求n的值. 2若/m+3/+(n+2)^2=0,求(1)m,n;(2)單項式mx^n+4y/9的係數和次數.

1-9/41a^3n-2 b^2n+3是六次單項式,求n的值. 2若/m+3/+(n+2)^2=0,求(1)m,n;(2)單項式mx^n+4y/9的係數和次數.

ab次數的和是6
所以3n-2+2n+3=6
5n=5
n=1
即m+3=n+2=0
m=-3,n=-2
單項式是-3x²y/9
所以次數是2+1=3
係數是-3/9=-1/3