So M= 1, M-N+ 1=0, that is, m = 1, n = 2 are arranged in descending order by the letter X as follows.
-2x^3+0.4x^2- 1/3*x^2+ 1
(2) It is known that the polynomial is cubic, and the polynomial given in the title is four terms, so one term must be zero, so M=2, and all the coefficients except 0.5xy (2n+6) * z 3 are less than 6, so 1+(2N+6)+3=6, and N=-2 is obtained.
(3) From the meaning of the question, 2m-8pi = 0,1+n+1+1= 2+3+3, so M=4Pi, N=5.
(π is π)
(4) Arranged in ascending order of X letters.
(5)-x+7,a+b^2,a/3+b,5x^3*y^2-3x^2*y^3,
8a 2-3ab is a polynomial.
-0.6a 2 * b,-1 1 is a monomial.