Question

解下列不等式:

(1)+n>3;(2).

Answer 1

(1) n≥5且n∈N.

(2) m=6.

解析:

(1)(n-3)(n-4)+n-3>0,

(n-3)(n-3)>0,

(n-3)²>0,

∴n≠3.又n-3≥2,

∴n≥5且n∈N.

(2)原不等式可化為

,

化簡得m²-15m+50<0,

(m-5)(m-10)<0,

5<m<10.

又即m≤6,

又m∈N,∴m=6.